Digital images and related methodologies

ABSTRACT

An imaging system, methodology, and various applications are provided to facilitate optical imaging performance. The system contains a sensor having one or more receptors and an image transfer medium to scale the sensor and receptors in accordance with resolvable characteristics of the medium, and as defined with certain ratios. Also provided are digital images that contain a plurality of image pixels, each image pixel containing information from about one sensor pixel, each sensor pixel containing substantially all information from about one associated diffraction limited spot in an object plane. Methods of making digital images are provided.

RELATED APPLICATIONS

[0001] This application is continuation-in-part of U.S. patentapplication of Ser. No. 10/758,836 which was filed Jan. 16, 2004entitled IMAGING SYSTEM AND METHODOLOGY, which is a continuation-in-partof U.S. patent application of Ser. No. 10/616,829 which was filed Jul.10, 2003 entitled IMAGING SYSTEM, METHODOLOGY, AND APPLICATIONSEMPLOYING RECIPROCAL SPACE OPTICAL DESIGN, which is acontinuation-in-part of U.S. patent application Ser. No. 10/189,326which was filed Jul. 2, 2002 entitled IMAGING SYSTEM AND METHODOLOGYEMPLOYING RECIPROCAL SPACE OPTICAL DESIGN, which is acontinuation-in-part of U.S. patent application Ser. No. 09/900,218,which was filed Jul. 6, 2001, entitled IMAGING SYSTEM AND METHODOLOGYEMPLOYING RECIPROCAL SPACE OPTICAL DESIGN now U.S. Pat. No. 6,664,528,all of which are incorporated herein by reference.

TECHNICAL FIELD

[0002] The present invention relates generally to image and opticalsystems, and more particularly to a system and method to facilitateimaging performance via an image transfer medium that projectscharacteristics of a sensor to an object field of view.

BACKGROUND OF THE INVENTION

[0003] Conventional analog microscopes and digital microscopes (eventhose with digital imaging cameras attached) are designed as they havebeen for the past few centuries to present images to the human eye usingmagnification (image size) as the primary parameter. Conventionalmicroscopes use a combination of an objective lens and a viewing lens(either eyepiece or “tube-lens”) to send the image of an object at adesired magnification to the image (or focal) plane where it is imagedby the human eye or a digital imaging device. The lenses define themagnification. The theoretical best resolution of such an optical systemcan be computed but is rarely, if ever actually, in practice achieved.Employing digital imaging devices on conventional microscopes furthercompromises image resolution and contrast for magnification. This hasalways meant striking a balance between “blur”, contrast, and size. Inother words, although modern digital imaging microscopes can make verygood and “pleasing” images, they do not really achieve the bestphysically possible.

[0004] The Nyquist criterion or sampling theorem states that for alimited bandwidth (band-limited) signal with maximum frequency (fmax),an equally spaced sampling frequency (fs) must be greater than twice themaximum frequency (fmax), i.e., fs>=2 fmax in order to have the signalbe uniquely reconstructed without aliasing. The frequency 2 fmax iscalled the Nyquist sampling rate. Half of this value, fmax, is sometimescalled the Nyquist frequency. The sampling theorem is considered to havebeen articulated by Nyquist in 1928 and mathematically proven by Shannonin 1949.

[0005] The Nyquist criterion is being applied to design digital imagingsystems. For example, in Nikon's MicroscopyU website, which provides aneducational forum for various aspects of optical microscopy, digitalimaging, and photomicrography, in a section titled “Digital CameraResolution Requirements for Optical Microscopy” it is stated that“[a]dequate resolution of a specimen imaged with the optical elements ofa microscope can only be achieved if at least two samples are made foreach resolvable unit, although many investigators prefer three samplesper resolvable unit to ensure sufficient sampling.” While Olympus'online Microscopy Resource Center echoes this statement in a sectiontitled “Electronic Imaging Detectors.” In another section of the websitetitled “Spatial Resolution in Digital Images”, it is further stated that“[t]o ensure adequate sampling for high-resolution imaging, an intervalof 2.5 to 3 samples for the smallest resolvable feature is suggested.”

SUMMARY OF THE INVENTION

[0006] The following presents a simplified summary of the invention inorder to provide a basic understanding of some aspects of the invention.This summary is not an extensive overview of the invention. It isintended to neither identify key or critical elements of the inventionnor delineate the scope of the invention. Its sole purpose is to presentsome concepts of the invention in a simplified form as a prelude to themore detailed description that is presented later.

[0007] The imaging systems of the present invention is specificallydesigned to present object data to a digital imaging device (such as aCCD or CMOS camera) and uses resolution as the primary design parameter.Matching projected pixel size in the object plane to the diffractionlimited spot size in the object plane, in accordance with one or moreparameters discussed below, provides the systems of the presentinvention with at least one of: gain in information retrieval, gain inremoving indeterminacy (or mitigation of indeterminacy), gain inbrightness per pixel, and gain in edge-sharpness compared toconventional imaging systems.

[0008] When projected pixel size in the object plane is matched to thediffraction limited spot size (smallest resolvable feature) in theobject plane, indeterminacy is mitigated. By mitigating indeterminacy, amore accurate reconstruction of spatial frequencies of interest isachieved compared to conventional imaging systems designed to place atleast 2.5 projected pixels into the diffraction limited spot.

[0009] An aspect of the present invention relates to digital images thatcontain a plurality of image pixels, each image pixel containinginformation from about one sensor pixel, each sensor pixel containingsubstantially all information from about one associated diffractionlimited spot in an object plane. Alternatively, the digital imagescontain a plurality of image pixels, each image pixel containingsubstantially all information comprised by one diffraction limited spotin an object plane.

[0010] Another aspect of the present invention relates to methods ofmaking digital images involving capturing object data on a pixelatedsensor, wherein substantially all object data comprised in eachdiffraction limited spot in the object plane is projected onto about oneassociated pixel on the pixelated sensor, and forming a digital imagecontaining image pixels, each image pixel displaying image data fromabout one sensor pixel. Alternatively, methods of forming digital imagesinvolve capturing object data on a sensor containing pixels, whereineach pixel on the sensor receives substantially all object datacomprised in an associated diffraction limited spot in the object planeand each pixel generates image data, and applying Nyquist criterion tothe image data generated by the pixels to form the digital image.

[0011] Yet another aspect of the present invention relates to methods ofincreasing the signal to noise ratio in making digital images involvingcollecting substantially all spatial frequencies of interest from adiffraction limited spot in the object plane by about one pixel on asensor. That is, a grid of diffraction limited spots in the object planeis substantially matched with a grid of projected pixels from a sensorin the object plane.

[0012] The following description and the annexed drawings set forth indetail certain illustrative aspects of the invention. These aspects areindicative, however, of but a few of the various ways in which theprinciples of the invention may be employed and the present invention isintended to include all such aspects and their equivalents. Otheradvantages and novel features of the invention will become apparent fromthe following detailed description of the invention when considered inconjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a schematic block diagram illustrating an imaging systemin accordance with an aspect of the present invention.

[0014]FIG. 2 is a diagram illustrating a k-space system design inaccordance with an aspect of the present invention.

[0015]FIG. 3 is a diagram of an exemplary system illustrating sensorreceptor matching in accordance with an aspect of the present invention.

[0016]FIG. 4 is a graph illustrating sensor matching considerations inaccordance with an aspect of the present invention.

[0017]FIG. 5 is a graph illustrating a Modulation Transfer Function inaccordance with an aspect of the present invention.

[0018]FIG. 6 is a graph illustrating a figure of merit relating to aSpatial Field Number in accordance with an aspect of the presentinvention.

[0019]FIG. 7 is a flow diagram illustrating an imaging methodology inaccordance with an aspect of the present invention.

[0020]FIG. 8 is a flow diagram illustrating a methodology for selectingoptical parameters in accordance with an aspect of the presentinvention.

[0021]FIG. 9 is a schematic block diagram illustrating an exemplaryimaging system in accordance with an aspect of the present invention.

[0022]FIG. 10 is a schematic block diagram illustrating a modularimaging system in accordance with an aspect of the present invention.

[0023]FIGS. 11-13 illustrate alternative imaging systems in accordancewith an aspect of the present invention.

[0024]FIGS. 14-18 illustrate exemplary applications in accordance withthe present invention.

[0025]FIG. 19 illustrates an automated inspection and/or manufacturingsystem and process in accordance with an aspect of the presentinvention.

[0026]FIG. 20 illustrates exemplary objects for inspection and/ormanufacturing in accordance with an aspect of the present invention.

[0027]FIG. 21 illustrates exemplary particle, material, and/or componentanalysis in accordance with an aspect of the present invention.

[0028]FIGS. 22 and 23 illustrate correlative imaging techniques inaccordance with an aspect of the present invention.

[0029]FIG. 24 illustrates a system for suspended particulatedetection/imaging in gaseous, liquid, transmissive and/or solid mediumsin accordance with an aspect of the present invention.

[0030]FIG. 25 is a top down view illustrating an exemplary sensor inaccordance with an aspect of the present invention.

[0031]FIG. 26 is a cross sectional view illustrating an exemplary sensorin accordance with an aspect of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0032] The inventors have discovered that a problem with employing theNyquist sampling theorem so as to require two to three pixels perdiffraction limited spot is that it is unknown which subset of thesuperset of spatial frequencies each pixel within a single diffractionlimited spot is receiving (the diffraction limited spot corresponds tothe superset of spatial frequencies of interest). Moreover, since thereis no means to properly correlate the respective subsets of spatialfrequencies received per pixel, indeterminacy results whenreconstructing the superset of spatial frequencies. This indeterminacyin image reconstruction results in a blurred image.

[0033] Put another way, the present invention, by matching projectedpixel size to a diffraction limited spot size in the object planeresults in a tuning of the lenses and pixels so that desired “spatial”frequencies of interest are received by respective pixels. Without suchmatching (as in conventional digital microscopy systems) adjoiningpixels may individually receive only a subset of “spatial frequencies”of interest thereby not taking full advantage of the capabilities of therespective pixels. Moreover, since the pixels are unaware (e.g., notcorrelated to) of what subset of the spatial frequencies they arerespectively receiving, indeterminacy results when trying to reconstructthe superset of spatial frequencies associated with a diffractionlimited spot as received by the set of adjoining pixels. Indeterminacymay cause a loss of image quality generally and specifically a loss ofintensity and loss in resolution.

[0034] On the other hand, by size matching individual pixels to thediffraction limited spot associated with a given set of lenses as in thepresent invention such indeterminacy is substantially mitigated sincethe superset of spatial frequencies of interest are substantiallyreceived by individual pixels. Because there are gaps between pixels inan array and thousands/millions of pixels being exposed to an imageprojection, there is typically some level of indeterminacy; however, thesubject invention significantly mitigates such indeterminacy as comparedto conventional digital imaging systems that fail to contemplate letalone address the advantages associated with the tuning that results bysize mapping of pixels to the diffraction limited spot as in the presentinvention. Another aspect of the present invention is a method ofreducing, mitigating, and/or eliminating indeterminacy in constructing adigital image by matching the diffraction limited spot size in theobject plane with the projected pixel size in the object plane.

[0035] Nyquist criterion has been applied in conventional digitalimaging systems before information is collected by requiring, forexample, three pixels per diffraction limited spot in an attempt, inpart, to measure the size of a set of spatial frequencies of interest.However, Nyquist criterion has nothing to do with how well a system canmeasure the size of a set of spatial frequencies of interest. Nyquistcriterion deals with how to distinguish between sets of spatialfrequencies of interest, and Nyquist criterion deals with measuring theperiodicity of spatial frequencies in a pixellated image. The presentinvention applies Nyquist criterion to collected image information (tothe spatial frequencies of interest after they are captured by thepixels). In other words, Nyquist sampling theorem is not a design rule(a rule to design an imaging system), but rather a useful tool ininterpreting collected image data. The present invention uses a designrule that maximizes the capture of image data or spatial frequencies ofinterest by capturing substantially all spatial frequencies of interestfrom a single diffraction limited spot on about a single pixel.

[0036] Moreover, since the spatial frequencies of interest also includean array of different colors (typically, for example, red, blue andgreen (RBG) or cyan, magenta, yellow (CMY)), conventional digitalimaging systems cannot provide for the level of color differentiationthat can be obtained by the present invention. That is, by using colorfilters on the sensor array, it is possible to determine if adjacentundifferentiated set of spatial frequencies of interest are differentcolors. If they are different colors, then it can be concluded with ahigh degree of confidence that the two sets of spatial frequencies ofinterest are provided by two distinct but adjacent sets of spatialfrequencies of interest, even though Nyquist application implies thatthere is no way of telling if the two adjacent sets of spatialfrequencies are spatially independent.

[0037] Since the subject invention provides for better reconstruction ofthe superset of spatial frequencies of interest as compared toconventional digital imaging systems, employment of color reconstructionalgorithms (as used by most digital microscopy systems) in accordancewith the present invention provides for improved color differentiationover conventional digital imaging systems employing like algorithmssince the superset of data analyzed by the algorithms is a closer matchto the actual spatial frequencies of interest as compared to thatprovided by conventional digital imaging systems.

[0038] Conventional digital imaging systems often use the Nyquistcriterion as a design rule, to the detriment of the collection of imageinformation. The imaging systems of the present invention collect all asmuch information possible in the most unambiguous way (by matchingdiffraction spot size to projected pixel size), and then apply rulessuch as the Nyquist criterion to analyze what is collected. Moreover,using color filters on the sensor array, an extra dimension ofinformation (color), especially in the undetermined case, is consideredwhen trying to determine whether adjacent pixels are distinct oridentical. The use of color filters does not change anything about theimage, or change the Nyquist criterion, it just allows more than onecriterion to be applied. In effect, the use of color filters is asupplement to the usual rules and can, in some circumstances, allow usto state that Nyquist-unresolved blobs are in fact independent andresolvable.

[0039] For purposes of this disclosure, the following definitions areemployed. A digital image is an image is generated from a pixelatedsensor, such as a CCD or CMOS sensor. The digital image may be viewed ona computer screen, paper, fabric, solid objects such as plastic objects,metal objects, wood objects, and the like, LCD screen/device, televisionmonitor, telephone, portable device, and the like. The digital image canalso be saved for subsequent viewing in a computer memory, a memorystick, a disc (floppy, CD, DVD, and the like), or any other digitalsaving means. A digital image is made up of image pixels (and thus imagepixels that form a digital image are different from sensor pixels thatcapture light and convert the light into electric signals). Generallyspeaking, the more image pixels a given digital image contains, the moredifficult it is to discern the presence of individual image pixels.Object data is embodied by light or spatial frequencies of interest thattravel from an object in an object plane through an image transfermedium, such as lenses, and is captured by or contacts sensor pixels.The object data may include information such as color and brightness ofthe object being imaged. The sensor pixel converts the object dataembodied in light to image data embodied by electrical signals. Theimage data is digital data containing information such as color andbrightness of the object being imaged.

[0040] In one aspect of the present invention, the design employs acombination of resolution lens and a matching lens, with a specificdigital imaging detector to define a desired resolution and match thedigital detector pixels in an approximate one-for-one with thephysically smallest resolvable detail (diffraction spot) as an opticalquantum of the object in the object plane. The uniqueresolution-optics-detector design relationship specifically defines animplicit spatial filter that results in maximizing resolution insubsequently formed images. The spatial filter keeps substantially allof the resolution information in the image and provides at least one ofsharp, high contrast, “non-noisy”, and bright digital images.Consequently, imaging instruments of the present invention can beextremely small and robust, can even use simple, large, high qualitylenses with long working distances, and other very attractive opticalparameters.

[0041] Each pixel of a digital imaging detector or sensor is essentiallya tiny photodiode that is sensitive to light and becomes electricallycharged in accordance with the strength of light that strikes it. Thepixel or photodiode converts light into electrical signals. That is, thepixels or photodiodes sense light and accumulate electrical charge inaccordance with the strength of light that strikes the pixels orphotodiodes. Generally speaking, any given pixel accumulates electricalcharge in direct proportion to the amount of light that strikes it.Photodiodes basically make use of photovoltaic effects to convert lightinto electrical charge.

[0042] On one hand, analog images, those made by traditional chemicalphotography, vary continuously, both spatially and tonally. On the otherhand, digital images are divided into a grid of discreet squares ofcolor/brightness called image pixels. That is, a single image pixel isthe smallest visual aspect of a digital image. This means that, whilethere is an infinite amount of information in an analog chemicalphotograph, a digital image is limited to the size and number of itsimage pixels.

[0043] Specific details and smooth curves are broken up by the gridsystem and each image pixel is assigned a monotone value. No matter howsmooth a digital image seems, it is always broken up into a grid. Thatmeans that even the smoothest looking curves are not really smooth upclose. This does not conversely imply that photographs taken withtraditional film can be blown up clearly an infinite amount of times.Analog photography definitely has limitations working against itsability to indefinitely magnify. For example, grain size of the analogimage can affect this. Grain size is a factor of both film speed and thequality of paper onto which the analog image is printed.

[0044] Each image pixel of a digital image is an approximated value forthat area of the digital image. The intensity or color for each imagepixel is represented by an integer number that specifies and assigns onevalue to that image pixel. Assigning individual integer values to partsof the image grid, is a process called quantization. The digital imageis essentially a collection of all the integers for all the individualimage pixels. The collection of these integers is called the rastergrid, and it is the means by which the information about the digitalimage is able to be stored in computer memory, sent to variouslocations, and understood by different technological equipment. Theprocess of approximating values for certain image pixels of the grid andthen assigning integer values is called filtering.

[0045] One aspect of resolution of a digital image refers to the densityof image pixel information per inch at a particular digital image size.This is often expressed as the number of image pixels per inch or dotsper inch, for instance 72 dpi. Concerns about improving resolution indigital images center around maximizing the number of image pixels thatform the form the digital image. The present invention improvesresolution in digital images by maximizing the amount of usefulinformation and minimizing the amount of useless/detrimental informationcontained in each image pixel.

[0046] In one embodiment, the digital images of the present inventioncontain at least about 2,000 image pixels. In another embodiment, thedigital images of the present invention contain at least about 10,000image pixels. In yet another embodiment, the digital images of thepresent invention contain at least about 100,000 image pixels. In stillyet another embodiment, the digital images of the present inventioncontain at least about 1,000,000 image pixels.

[0047] In one aspect of the present invention, a digital image is formedor contains a plurality of image pixels, where each image pixel containsinformation from about one sensor pixel, and each sensor pixel containsinformation from about one diffraction limited spot in an object plane.That is, each image pixel of the digital image contains or displaysimage data generated by about one associated sensor pixel, and eachsensor pixel captures object data contained in about one associateddiffraction limited spot in an object plane. Substantially all spatialfrequencies of interest contained in a diffraction limited spot in anobject plane are projected onto an associated sensor pixel, and thesensor pixel converts the spatial frequencies of interest embodied bylight into an electric signal containing digital image data. A processormay facilitate displaying digital image data from a plurality of sensorpixels as a digital image. Unlike conventional imaging systems which,for example, project light in a diffraction limited spot onto threesensor pixels, the present invention for example projects light fromabout one diffraction limited spot onto about one sensor pixel (asexplained more fully elsewhere, the maximum ratio range of thediffraction limited spot to projected pixel size of the imaging systemof the present invention is about 1.9:1 to about 1:1.9, and other sizingparameters are further discussed). Consequently, for example, digitalimage quality is maximized as each image pixel of the digital imagecontains substantially all information comprised by one diffractionlimited spot in an object plane.

[0048] Substantially all spatial frequencies of interest contained in adiffraction limited spot, substantially all object data contained in adiffraction limited spot, and substantially all information contained ina diffraction limited spot means enough data or information to achievethe projected pixel size-diffraction spot size matching describedherein. In one embodiment, substantially all spatial frequencies ofinterest contained in a diffraction limited spot, substantially allobject data contained in a diffraction limited spot, and substantiallyall information contained in a diffraction limited spot means at leastabout 60% of all spatial frequencies of interest, object data, orinformation from one diffraction limited spot. In another embodiment,substantially all spatial frequencies of interest contained in adiffraction limited spot, substantially all object data contained in adiffraction limited spot, and substantially all information contained ina diffraction limited spot means at least about 70% of all spatialfrequencies of interest, object data, or information from onediffraction limited spot. In yet another embodiment, substantially allspatial frequencies of interest contained in a diffraction limited spot,substantially all object data contained in a diffraction limited spot,and substantially all information contained in a diffraction limitedspot means at least about 80% of all spatial frequencies of interest,object data, or information from one diffraction limited spot. In stillyet another embodiment, substantially all spatial frequencies ofinterest contained in a diffraction limited spot, substantially allobject data contained in a diffraction limited spot, and substantiallyall information contained in a diffraction limited spot means at leastabout 90% of all spatial frequencies of interest, object data, orinformation from one diffraction limited spot. In yet anotherembodiment, substantially all spatial frequencies of interest containedin a diffraction limited spot, substantially all object data containedin a diffraction limited spot, and substantially all informationcontained in a diffraction limited spot means at least about 95% of allspatial frequencies of interest, object data, or information from onediffraction limited spot. Substantially all spatial frequencies ofinterest contained in a diffraction limited spot, substantially allobject data contained in a diffraction limited spot, and substantiallyall information contained in a diffraction limited spot does not meansubstantially all spatial frequencies of interest, object data, orinformation from two or more diffraction limited spots.

[0049] In another aspect of the present invention, a method of making adigital image involves capturing object data on a pixelated sensor,wherein substantially all object data contained in a diffraction limitedspot in the object plane is projected onto about one pixel on thepixelated sensor. That is, each sensor pixel receives substantially allobject data from about one diffraction limited spot in the object plane(again, as explained more fully elsewhere, the maximum ratio range ofthe diffraction limited spot to projected pixel size of the imagingsystem of the present invention is about 1.9:1 to about 1:1.9, and othersizing parameters are further discussed). This methodology is unlikeconventional imaging systems where, for example, each sensor pixelreceives one-fifth to one-ninth of object data from one diffractionlimited spot. As the sensor pixels of the pixelated sensor receivesobject data, the object data is transformed into image data embodied inan electrical signal. The image data from each sensor pixel (the datawhich corresponds to substantially all data contained in an associateddiffraction limited spot) is used to generate a corresponding imagepixel, and the display of all of the image pixels forms the digitalimage. Simply put, the digital image contains image pixels, where eachimage pixel displays image data from about one sensor pixel.

[0050] In yet another aspect of the present invention, a method offorming a digital image involves capturing object data on a sensorcontaining pixels, wherein each pixel on the sensor receivessubstantially all object data contained in an associated diffractionlimited spot in the object plane and each pixel generates image data. Asor after each pixel generates image data, the Nyquist criterion isapplied to the image data generated by the pixels to form the digitalimage. This methodology is unlike conventional imaging systems where,for example, the Nyquist criterion is applied to design the imagingsystem and collect object data. Conventional imaging systems apply theNyquist criterion by capturing one-fifth to one-ninth of object datafrom each diffraction limited spot by a single sensor pixel. The presentinventors, however, do not use the Nyquist criterion to design animaging system and/or collect object data. Instead, the presentinventors use the Nyquist criterion to interpret the object and/or imagedata. Consequently, the imaging systems of the present inventionmaximize the information collected, and then apply the Nyquist criterionto a maximum amount of image information thereby affording improvedquality digital images.

[0051] Contrast is greatly improved in this respect compared toconventional imaging systems that capture one-fourth to one-ninth ofobject data from each diffraction limited spot by a single sensor pixel,because substantially all object data contained in an associateddiffraction limited spot is captured by each pixel. This means that inthe imaging systems of the present invention, each pixel receives fromabout 5 to about 9 times the amount of light that pixels receive inconventional systems. Since pixels generate electrical charge in directproportion to the amount of light that strikes it, the pixels thatreceive light in the imaging systems of the present invention receivemuch more light than corresponding pixels in conventional systems.Furthermore, since each pixel of the present invention receives fromabout 5 to about 9 times the amount of light than pixels receive inconventional systems, the difference between adjacent light and darkpixels of the present invention is greater than adjacent light and darkpixels in conventional systems. As a result, contrast in particular isdramatically improved in the imaging systems of the present inventionthat have pixel-diffraction limited spot matching compared toconventional systems that require placing at least 2.5 and preferably 3projected pixels across a diffraction limited spot in the object plane.

[0052] In still yet another aspect of the present invention, andparticularly in light of the discussion of contrast improvement, amethod of increasing the signal to noise ratio in making a digital imageis provided. The method of increasing the signal to noise ratio involvescollecting substantially all spatial frequencies of interest from adiffraction limited spot in the object plane by about one pixel on asensor. That is, each pixel on a sensor captures substantially all lightfrom an associated diffraction limited spot in the object plane. Sinceeach pixel receives from about 5 to about 9 times the amount of lightthan pixels receive in conventional systems, the difference betweensignals and noise is correspondingly improved. Elimination of noise inthe imaging systems of the present invention is much easier andconducted with greater accuracy compared to attempts to eliminate noisein conventional imaging systems.

[0053] The present invention relates to a system and methodology thatfacilitates imaging performance of optical imaging systems. In regard toseveral optical and/or imaging system parameters, many orders ofperformance enhancement can be realized over conventional systems (e.g.,greater effective resolved magnification, larger working distances,increased absolute spatial resolution, increased spatial field of view,increased depth of field, Modulation Transfer Function of about 1, oilimmersion objectives and eye pieces not required). This is achieved byadapting an image transfer medium (e.g., one or more lenses, fiberoptical media, or other media) to a sensor having one or more receptors(e.g., photodetectors, pixels) such that the receptors of the sensor areeffectively scaled (e.g., “mapped”, “sized”, “projected”, “matched”,“reduced”) to occupy an object field of view at about the scale or sizeassociated with a diffraction limited point or spot within the objectfield of view. Thus, a band-pass filtering of spatial frequencies inwhat is known as Fourier space or “k-space” is achieved such that theprojected size (projection in a direction from the sensor toward objectspace) of the receptor is filled in k-space.

[0054] In other words, the image transfer medium is adapted, configuredand/or selected such that a transform into k-space is achieved, whereinan a priori design determination causes k-space or band-pass frequenciesof interest to be substantially preserved throughout and frequenciesabove and below the k-space frequencies to be mitigated. It is notedthat the frequencies above and below the k-space frequencies tend tocause blurring and contrast reduction and are generally associated withconventional optical system designs which define intrinsic constraintson a Modulation Transfer Function and “optical noise”. This furtherillustrates that the systems and methods of the present invention are incontravention or opposition to conventional geometric paraxial raydesigns. Consequently, many known optical design limitations associatedwith conventional systems are mitigated by the present invention.

[0055] According to one aspect of the present invention, a “k-space”design, system and methodology is provided which defines a“unit-mapping” of the Modulation Transfer Function (MTF) of an objectplane to image plane relationship. The k-space design projects imageplane pixels or receptors forward to the object plane to promote anoptimum theoretical relationship. This is defined by numeric ratios andsizes of projected image sensor receptors and projected object planeunits (e.g., units defined by smallest resolvable points or spots in anoptical or image transfer medium) that are matched according to theprojected receptor size. The k-Space design defines “unit-mapping” or“unit-matching” acts as an effective “Intrinsic Spatial Filter” whichimplies that spectral components of both an object and an image ink-space (also referred to as “reciprocal-space”) are substantiallymatched or quantized. Advantages provided by the k-space design resultin a system and methodology capable of much higher effective resolvedmagnification with concomitantly related and much increased Field OfView, Depth Of Field, Absolute Spatial Resolution, and Working Distancesutilizing dry objective lens imaging, for example, and without employingconventional oil immersion techniques having inherent intrinsiclimitations to the aforementioned parameters.

[0056] The present invention relates to an optical and/or imaging systemand methodology. According to one aspect of the present invention, ak-space filter is provided that can be configured from an image transfermedium such as optical media that correlates image sensor receptors toan optical or image transfer medium. A variety of illumination sourcescan also be employed to achieve one or more operational goals and forversatility of application. The k-space design of the imaging system ofthe present invention promotes capture and analysis (e.g., automatedand/or manual) of images having a high Field Of View (FOV) atsubstantially high Effective Resolved Magnification as compared toconventional systems. This can include employing a small NumericalAperture (NA) associated with lower magnification objective lenses toachieve very high Effective Resolved Magnification. As a consequence,images having a substantially large Depth Of Field (DOF) at very highEffective Resolved Magnification are also realized. The k-space designalso facilitates employment of homogeneous illumination sources that aresubstantially insensitive to changes in position, thereby improvingmethods of examination and analysis.

[0057] According to another aspect of the present invention, anobjective lens to object distance (e.g., Working Distance) can bemaintained in operation at low and high power effective resolvedmagnification imaging, wherein typical spacing can be achieved at about0.1 mm or more and about 20 mm or less, as opposed to conventionalmicroscopic systems which can require significantly smaller (as small as0.01 mm) object to objective lens distances for comparable (e.g.,similar order of magnitude) Effective Resolved Magnification values. Inanother aspect, the Working Distance is about 0.5 mm or more and about10 mm or less. It is to be appreciated that the present invention is notlimited to operating at the above working distances. In many instancesthe above working distances are employed, however, in some instances,smaller or larger distances are employed. It is further noted that oilimmersion or other Index of Refraction matching media or fluids forobjective lenses are generally not required (e.g., substantially noimprovement to be gained) at one or more effective image magnificationlevels of the present invention yet, still exceeding effective resolvedmagnification levels achievable in conventional microscopic opticaldesign variations including systems employing “infinity-corrected”objective lenses.

[0058] The k-space design of the present invention defines that a small“Blur Circle” or diffraction limited point/spot at the object plane isdetermined by parameters of the design to match projected image sensorreceptors or projected pixels in the object plane with a ratio definedcorrespondence by “unit-mapping” of object and image spaces forassociated object and image fields. This enables the improvedperformance and capabilities of the present invention. One possibletheory of the k-space design results from the mathematical concept thatsince the Fourier Transform of both an object and an image is formed ink-space (also called “reciprocal space”), the sensor is mapped to theobject plane in k-space via optical design techniques and componentplacement in accordance with the present invention. It is to beappreciated that a plurality of other transforms or models can beutilized to configure and/or select one or more components in accordancewith the present invention. For example, wavelet transforms, Laplace(s-transforms), z-transforms as well as other transforms can besimilarly employed.

[0059] The k-space design methodology is unlike conventional opticalsystems designed according to geometric, paraxial ray-trace andoptimization theory, since the k-space optimization facilitates that thespectral components of the object (e.g., tissue sample, particle,semiconductor) and the image are the same in k-space, and thusquantized. Therefore, there are substantially no inherent limitationsimposed on a Modulation Transfer Function (MTF) describing contrastversus resolution and absolute spatial resolution in the presentinvention. Quantization, for example, in k-space yields a substantiallyunitary Modulation Transfer Function not realized by conventionalsystems. It is noted that high MTF, Spatial Resolution, and effectiveresolved image magnification can be achieved with much lowermagnification objective lenses with desirable lower Numerical Apertures(e.g., generally less than about 50× with a numerical aperture ofgenerally less than about 0.7) through “unit-mapping” of projectedpixels in an “Intrinsic Spatial Filter” provided by the k-space design.

[0060] If desired, “infinity-corrected” objectives can be employed withassociated optical component and illumination, as well as spectrumvarying components, polarization varying components, and/or contrast orphase varying components. These components can be included in an opticalpath-length between an objective and the image lens within an “infinityspace”. Optical system accessories and variations can thus be positionedas interchangeable modules in this geometry. The k-space design, incontrast to conventional microscopic imagers that utilize“infinity-corrected” objectives, enables the maximum optimization of theinfinity space geometry by the “unit-mapping” concept. This implies thatthere is generally no specific limit to the number of additionalcomponents that can be inserted in the “infinity space” geometry as inconventional microscopic systems that typically specify no more than 2additional components without optical correction.

[0061] The present invention also enables a “base-module” design thatcan be configured and reconfigured in operation for a plurality ofdifferent applications if necessary to employ transmissive and/orreflected illumination, if desired. This includes substantially alltypical machine vision illumination schemes (e.g., darkfield,brightfield, phase-contrast), and other microscopic transmissivetechniques (Kohler, Abbe), in substantially any offset and can includeEpi-illumination—and variants thereof. The systems of the presentinvention can be employed in a plurality of opto-mechanical designs thatare robust since the k-space design is substantially not sensitive toenvironmental and mechanical vibration and thus generally does notrequire heavy structural mechanical design and isolation from vibrationassociated with conventional microscopic imaging instruments. Otherfeatures can include digital image processing, if desired, along withstorage (e.g., local database, image data transmissions to remotecomputers for storage/analysis) and display of the images produced inaccordance with the present invention (e.g., computer display, printer,film, and other output media). Remote signal processing of image datacan be provided, along with communication and display of the image datavia associated data packets that are communicated over a network orother medium, for example.

[0062] Moreover, images that are created in accordance with the presentinvention can be stored and/or transmitted with other digitalinformation (e.g., audio data, other images, medical histories, productinformation, analysis information, and so forth). For example, an imagemay have associated voice-encoded data describing one or more aspects ofthe image or images contained as part of a data package that can bestored locally and/or transmitted across a network for remote storageand/or further analysis. In one specific example, an image created inaccordance with the present invention can be transmitted to a remotelocation, wherein the image is further analyzed (e.g., medical orproduct specialist analyzes received image on a computer or imagedisplay). After analysis, a voice encoding or related data is appendedor encoded with the received image and then transmitted back to theoriginating location (or other location), wherein the image andresultant encoded analysis can be reviewed. As can be appreciated,substantially any type of digital information can be stored and/ortransmitted with images that are created in accordance with the presentinvention.

[0063] Also, as will be apparent from the following description, thepresent invention can be economically implemented in a plurality ofvarious packages including integrated imaging/computing systems that areemployed to analyze various samples. Such systems include handhelddevices, notebook computers, laptops, personal digital assistants, andso forth that are adapted with the imaging concepts described herein.

[0064] Referring initially to FIG. 1, an imaging system 10 isillustrated in accordance with an aspect of the present invention. Theimaging system 10 includes a sensor 20 having one or more receptors suchas pixels or discrete light detectors (See e.g., illustrated below inFIG. 3) operably associated with an image transfer medium 30. The imagetransfer medium 30 is adapted or configured to scale the proportions ofthe sensor 20 at an image plane established by the position of thesensor 20 to an object field of view illustrated at reference numeral34. A planar reference 36 of X and Y coordinates is provided toillustrate the scaling or reduction of the apparent or virtual size ofthe sensor 20 to the object field of view 34. Direction arrows 38 and 40illustrate the direction of reduction of the apparent size of the sensor20 toward the object field of view 34.

[0065] The object field of view 34 established by the image transfermedium 30 is related to the position of an object plane 42 that includesone or more items under microscopic examination (not shown). It is notedthat the sensor 20 can be substantially any size, shape and/ortechnology (e.g., digital sensor, analog sensor, Charge Coupled Device(CCD) sensor, CMOS sensor, Charge Injection Device (CID) sensor, anarray sensor, a linear scan sensor) including one or more receptors ofvarious sizes and shapes, the one or more receptors being similarlysized or proportioned on a respective sensor to be responsive to light(e.g., visible, non-visible, “light”, “radiation”, or other such“visible” or “invisible” or “non-visible” hereafter meaning radiation ofsome desired wavelength optically directed. That is: radiation of anyparticular wavelength whose optical path, direction, and/or path lengthis altered by means of an optical medium, surface, material, component,or components, or other such means suitable to radiation of thatwavelength in the configuration or configurations pertaining to thedirection of such radiation to achieve the desired characteristics inaccordance with the present invention) received from the items underexamination in the object field of view 34.

[0066] As light is received from the object field of view 34, the sensor20 provides an output 44 that can be directed to a local or remotestorage such as a memory (not shown) and displayed from the memory via acomputer and associated display, for example, without substantially anyintervening digital processing (e.g., straight bit map from sensormemory to display), if desired. It is noted that local or remote signalprocessing of the image data received from the sensor 20 can also occur.For example, the output 44 can be converted to electronic data packetsand transmitted to a remote system over a network and/or via wirelesstransmissions systems and protocols for further analysis and/or display.Similarly, the output 44 can be stored in a local computer memory beforebeing transmitted to a subsequent computing system for further analysisand/or display.

[0067] The scaling provided by the image transfer medium 30 isdetermined by a novel k-space configuration or design within the mediumthat promotes predetermined k-space frequencies of interest andmitigates frequencies outside the predetermined frequencies. This hasthe effect of a band-pass filter of the spatial frequencies within theimage transfer medium 30 and notably defines the imaging system 10 interms of resolution rather than magnification. As will be described inmore detail below, the resolution of the imaging system 10 determined bythe k-space design promotes a plurality of features in a displayed orstored image such as having high effective resolved magnification, highabsolute spatial resolution, large depth of field, larger workingdistances, and a unitary Modulation Transfer Function as well as otherfeatures.

[0068] In order to determine the k-space frequencies, a size or a“pitch” or spacing is deteteined between adjacent receptors on thesensor 20, the pitch related to the center-to-center distance ofadjacent receptors and about the size or diameter of a single receptor.The pitch of the sensor 20 defines the Nyquist “cut-off” frequency bandof the sensor. It is this frequency band that is promoted by the k-spacedesign, whereas other frequencies are mitigated. In order to illustratehow scaling is determined in the imaging system 10, a small ordiffraction limited spot or point 50 is illustrated at the object plane42. The diffraction limited point 50 represents the smallest resolvableobject determined by optical characteristics within the image transfermedium 30 and is described in more detail below. A scaled receptor 54,depicted in front of the field of view 34 for exemplary purposes, andhaving a size determined according to the pitch, for example, of thesensor 20, is matched or scaled to have a size ratio in the object fieldof view 34 as the diffraction limited point 50 which is a function ofthe resolvable characteristics of the image transfer medium 30.

[0069] In other words, the size of any given receptor at the sensor 20is effectively reduced in size via the image transfer medium 30 to havea size (or matched in size) within a ratio of the size of thediffraction limited point 50. This also has the effect of filling theobject field of view 34 with substantially all of the receptors of thesensor 20, the respective receptors being suitably scaled to be similarin size to the diffraction limited point 50. As will be described inmore detail below, the matching/mapping of sensor characteristics to thesmallest resolvable object or point within the object field of view 34defines the imaging system 10 in terms of absolute spatial resolutionand thus, enhances the operating performance of the system.

[0070] An illumination source 60 can be provided with the presentinvention in order that photons from the source can be transmittedthrough and/or reflected from objects in the field of view 34 to enableactivation of the receptors in the sensor 20. It is noted that thepresent invention can potentially be employed without an illuminationsource 60 if potential self-luminous objects (e.g., fluorescent orphosphorescent biological or organic material sample, metallurgical,mineral, and/or other inorganic material and so forth) emit enoughradiation to activate the sensor 60. Light Emitting Diodes, however,provide an effective illumination source 60 in accordance with thepresent invention. Substantially any illumination source 60 can beapplied including coherent and non-coherent sources, visible andnon-visible wavelengths. However, for non-visible wavelength sources,the sensor 20 and if necessary, the optical media of the image transfermedium 30 would also be suitably adapted. For example, for an infraredor ultraviolet source, an infrared or ultraviolet sensor 20 and IR or UVsuitable optical components in the image transfer medium 30 would beemployed, respectively. Other illumination sources 60 can includewavelength-specific lighting, broad-band lighting, continuous lighting,strobed lighting, Kohler illumination, Abbe illumination, phase-contrastillumination, darkfield illumination, brightfield illumination, and Epiillumination. Transmissive or reflective lighting techniques (e.g.,specular and diffuse) can also be applied.

[0071] Referring now to FIG. 2, a system 100 illustrates an imagetransfer medium in accordance with an aspect of the present invention.The image transfer medium 30 depicted in FIG. 1 can be providedaccording to the k-space design concepts described above and moreparticularly via a k-space filter 110 adapted, configured and/orselected to promote a band of predetermined k-space frequencies 114 andto mitigate frequencies outside of this band. This is achieved by, forexample, determining a pitch “P”—which is the distance between adjacentreceptors 116 in a sensor (not shown) and sizing optical media withinthe filter 110 such that the pitch “P” of the receptors 116 is matchedin size with a diffraction-limited spot 120, other pixel size parametersmay be employed. The diffraction-limited spot 120 can be determined fromthe optical characteristics of the media in the filter 110. For example,the Numerical Aperture of an optical medium such as a lens defines thesmallest object or spot that can be resolved by the lens. The filter 110performs a k-space transformation such that the size of the pixel iseffectively matched, “unit-mapped”, projected, correlated, and/orreduced to the size or scale of the diffraction limited spot 120, inaccordance with ratios provided below.

[0072] It is to be appreciated that a plurality of opticalconfigurations can be provided to achieve the k-space filter 110. Onesuch configuration can be provided by an aspherical lens 124 adaptedsuch to perform the k-space transformation and reduction from sensorspace to object space. Yet another configuration can be provided by amultiple lens arrangement 128, wherein the lens combination is selectedto provide the filtering and scaling. Still yet another configurationcan employ a fiber optic taper 132 or image conduit, wherein multipleoptical fibers or array of fibers are configured in a funnel-shape toperform the mapping of the sensor to the object field of view. It isnoted that the fiber optic taper 132 is generally in physical contactbetween the sensor and the object under examination (e.g., contact withmicroscope slide). Another possible k-space filter 110 arrangementemploys a holographic (or other diffractive or phase structure) opticalelement 136, wherein a substantially flat optical surface is configuredvia a hologram (or other diffractive or phase structure) (e.g.,computer-generated, optically generated, and/or other method) to providethe mapping in accordance with the present invention.

[0073] The k-space optical design as enabled by the k-space filter 110is based upon the “effective projected pixel size” of the sensor, whichis a figure derived from following (“projecting”) the physical size ofthe sensor array elements back through the optical system to the objectplane. In this manner, conjugate planes and optical transform spaces arematched to the Nyquist cut-off of the effective receptor or pixel size.This maximizes the effective resolved image magnification and the FieldOf View as well as the Depth Of Field and the Absolute SpatialResolution. Thus, a novel application of optical theory is provided thatdoes not rely on conventional geometric optical design parameters ofparaxial ray-tracing which govern conventional optics and imagingcombinations. This can further be described in the following manner.

[0074] A Fourier transform of an object and an image is formed (by anoptical system) in k-space (also referred to as “reciprocal-space”). Itis this transform that is operated on for image optimization by thek-space design of the present invention. For example, the optical mediaemployed in the present invention can be designed with standard,relatively non-expensive “off-the-shelf” components having aconfiguration which defines that the object and image space are“unit-mapped” or “unit-matched” for substantially all image and objectfields. A small Blur-circle or diffraction-limited spot 120 at theobject plane is defined by the design to match the projected pixel sizesin the object plane with ratios described below and thus the Fouriertransforms of pixelated arrays can be matched. This implies that,optically by design, the Blur-circle is scaled to the projected size ofthe receptor or to the projected pixel size. The present invention isdefined such that it constructs an Intrinsic Spatial Filter such as thek-space filter 110. Such a design definition and implementation enablesthe spectral components of both the object and the image in k-space tobe about the same or quantized. This also defines that the ModulationTransfer Function (MTF) (the comparison of contrast to spatialresolution) of the sensor is at least substantially matched to the MTFof the object Plane.

[0075]FIG. 3 illustrates an optical system 200 in accordance with anaspect of the present invention. The system 200 includes a sensor 212having a plurality of receptors or sensor pixels 214. For example, thesensor 212 is an M by N array of sensor pixels 214, having M rows and Ncolumns (e.g., 640×480, 512×512, 1280×1024, 2268×1536, 1420×1064, and soforth), M and N being integers respectively. Although a rectangularsensor 212 having generally square pixels is depicted, it is to beunderstood and appreciated that the sensor can be substantially anyshape (e.g., circular, elliptical, hexagonal, rectangular, and soforth). It is to be further appreciated that respective pixels 214within the array can also be substantially any shape or size, the pixelsin any given array 212 being similarly sized and shaped in accordancewith an aspect of the present invention.

[0076] The sensor 212 can be substantially any technology (e.g., digitalsensor, analog sensor, Charge Coupled Device (CCD) sensor, CMOS sensor,Charge Injection Device (CID) sensor, an array sensor, a linear scansensor) including one or more receptors (or pixels) 214. According toone aspect of the present invention, each of the pixels 214 is similarlysized or proportioned and responsive to light (e.g., visible,non-visible) received from the items under examination, as describedherein.

[0077] The sensor 212 is associated with a lens network 216, which isconfigured based on performance requirements of the optical system andthe pitch size of sensor 212. The lens network 216 is operative to scale(or project) proportions (e.g., pixels 214) of the sensor 212 at animage plane established by the position of the sensor 212 to an objectfield of view 220 in accordance with an aspect of the present invention.The object field of view 220 is related to the position of an objectplane 222 that includes one or more items (not shown) under examination.

[0078] Departing from the specifics of FIG. 3, the most common pixel orphotodetector shapes are squares and rectangles. However, the pixels canhave any shape so long as it retains its function. Additional shapes ofpixels include hexagons, octagons, and other polygons, circles, ovals,ellipses, and the like. The size of the pixels typically varies fromsensor to sensor.

[0079] There are a number of ways in which to measure pixel size.Typically, when not specified otherwise, pixel size is represented bypixel pitch, which the distance between the centers of adjacent pixels.Pixel size can be represented by area (surface area of the top surfaceor light receiving/detecting surface of a pixel), pixel length, pixelwidth, pixel diameter, and the like. In the case of stacked pixels,pixel size is determined based on a stack to stack basis. If pixels in astack are of different sizes, then either the average of the differentsizes, the largest of the different sizes, or the smallest of thedifferent sizes is used to determine pixel size. This is because, whencompared to the diffraction limited spot size in the object plane, it isthe projected pixel size in the object plane that is employed.

[0080] In one aspect of the invention, the pixel size is one of a pixelpitch (for any pixels), pixel length (for square pixels), and pixelwidth (for rectangular pixels), that is about 0.1 microns or more andabout 20 microns or less. In another aspect of the invention, the pixelsize is one of a pixel pitch (for any pixels), pixel length (for squarepixels), and pixel width (for rectangular pixels), that is about 0.25microns or more and about 15 microns or less. In yet another aspect ofthe invention, the pixel size is one of a pixel pitch (for any pixels),pixel length (for square or rectangular pixels), and pixel width (forsquare or rectangular pixels), that is about 0.5 microns or more andabout 10 microns or less. In still yet another aspect of the invention,the pixel size is one of a pixel pitch (for any pixels), pixel length(for square or rectangular pixels), and pixel width (for square orrectangular pixels), that is about 4 microns or more and about 9 micronsor less.

[0081] In one aspect of the invention, the pixel size is pixel area,that is about 0.01 microns² or more and about 600 microns² or less. Inanother aspect of the invention, the pixel size is pixel area that isabout 0.1 microns² or more and about 200 microns² or less. In yetanother aspect of the invention, the pixel size is pixel area that isabout 0.5 microns² or more and about 100 microns² or less. In still yetanother aspect of the invention, the pixel size is pixel area that isabout 1 microns² or more and about 50 microns² or less.

[0082] In one aspect of the invention, the projected pixel size in theobject plane is one of a projected pixel pitch (for any pixels),projected pixel length (for square pixels), and projected pixel width(for rectangular pixels), that is about 0.01 microns or more and about20 microns or less. In another aspect of the invention, the projectedpixel size in the object plane is one of a projected pixel pitch (forany pixels), projected pixel length (for square pixels), and projectedpixel width (for rectangular pixels), that is about 0.05 microns or moreand about 15 microns or less. In yet another aspect of the invention,the projected pixel size in the object plane is one of a projected pixelpitch (for any pixels), projected pixel length (for square pixels), andprojected pixel width (for rectangular pixels), that is about 0.1microns or more and about 10 microns or less. In still yet anotheraspect of the invention, the projected pixel size in the object plane isone of a projected pixel pitch (for any pixels), projected pixel length(for square pixels), and projected pixel width (for rectangular pixels),that is about 0.5 microns or more and about 5 microns or less.

[0083] In one aspect of the invention, the projected pixel size isprojected pixel area that is about 0.0003 microns² or more and about 600microns² or less. In another aspect of the invention, the projectedpixel size is projected pixel area that is about 0.001 microns² or moreand about 200 microns² or less. In yet another aspect of the invention,the projected pixel size is projected pixel area that is about 0.01microns² or more and about 100 microns² or less. In still yet anotheraspect of the invention, the projected pixel size is projected pixelarea that is about 0.1 microns² or more and about 50 microns² or less.

[0084] Specific examples of pixel parameters include a pixel pitch,pixel length, pixel width, and/or pixel diameter of about 20 microns,about 12.5 microns, about 12 microns, about 11 microns, about 10.8microns, about 10 microns, about 9.9 microns, about 9.12 microns, about8.8 microns, about 7.9 microns, about 7.8 microns, about 7.4 microns,about 5.4 microns, about 5 microns, about 4 microns, about 3.5 microns,and about 2.7 microns.

[0085] The sensors may have pixels where substantially all pixels havesubstantially the same shape and/or size. The sensors may also havepixels where one subset of pixels has a first shape and/or first sizeand a second subset of pixels has a second shape and/or second size.That is, the sensors may have pixels of at least two different shapesand/or at least two different sizes. Sensors with different sized pixelsmay have pixels that have different sizes, or may have certain groups ofpixels that are combined to make pixels of apparent different sizes. Ofcourse, suitable control circuitry can be employed to use image datafrom discrete sets of pixels.

[0086] Referring to FIG. 25, a sensor 2500 is shown with four regions2502, 2504, 2506, and 2508. Each of the four regions 2502, 2504, 2506,and 2508 has a discrete and different pixel size. That is, region 2502has pixels 2510 of a first size and shape, region 2504 has pixels 2512of a second size, region 2506 has pixels 2514 of a third size and secondshape, region 2508 has pixels 2516 of a fourth size. Such a sensor canbe employed in an imaging system that has a turret of four objectivelenses, wherein each of the four objective lenses has a diffractionlimited spot size in the object field of view matched with a respectiveone of the pixel sizes of the four pixel regions. The control circuitrycan be employed to use data from a discrete set of pixels that have asize substantially matched with the size of the diffraction limited spotof one of the lenses.

[0087] The sensor may have a planar array of pixels where the pixels areoriented adjacent each other horizontally (unstacked), or an array ofstacks of pixels may be provided on the sensor substrate. In the case ofunstacked pixels, pixels having an ability to capture a discretewavelength (or wavelength range) of light alternate throughout thesensor (to form, for example, a three colored checkerboard). In the caseof stacked pixels (multilayered photodetectors), often three or fourpixels are stacked, each having an ability to capture a discretewavelength (or wavelength range) of light, such as red, green, and blueor cyan, magenta, and yellow in a three layered design and red, green,blue, and cyan in a four layered design. Also in the case of stackedpixels, each stack may contain pixels of the same size and/or shape ordifferent sizes and/or shapes.

[0088] In embodiments where the sensor contains at least two arrays orareas having different pixel sizes, the arrays or areas may also bedisposed so as to allow the direct indexing, or movement, or selectionthrough optical path directing or mechanical directing, or other suchmeans to configure any given discrete sensor array or area so that itsentire discrete array or area or dimension is configured with theappropriate objective lens for mapping both the diffraction spot size topixel size and the discrete sensor array or area to the entire objectplane field of view in order to maximize the Absolute Spatial Resolutionper pixel in the object plane. It is further defined that such groups,arrays, combinations, or other such assemblies comprising arrays ofdiscrete sensor areas as described may be separated, individual sensorchips or integrated groupings on single substrates or mounts so disposedas to allow the selectability of the sensor group or array to beconfigured with the appropriate objective lens for mapping both thediffraction spot size to pixel size and the discrete sensor array orarea to the object field of view. In other words, in order to maximizethe Absolute Spatial Resolution of an image, the number of pixelsprojected within the object field of view is maximized, in addition tomatching diffraction spot size in the object plane and pixel size.

[0089] Referring to FIG. 26, another sensor 2600 is shown having stacks2602 of pixels. In this case, a stack 2602 of four pixels 2604, 2606,2608, and 2610(or four photodetectors that constitute a pixel stack2602) is shown. When using a sensor having stacked pixels, the pixels orphotodetectors of a stack may have the same or different sizes and/orshapes. FIG. 26 shows a stack 2602 having pixels 2604, 2606/2608, and2610 having different sizes.

[0090] Examples of commercially available sensors, such as CCD and CMOSsensors, are those made by Foveon, Toshiba, Elisnet, Thomson, Sony,Samsung Semiconductor, Matsushita Electronics, Philips, Sharp, NEC,Motorola, Texas Instruments, EG&G Reticon, Kodak, Fairchild Imaging,CMOS Sensor Inc., Silicon Video Inc., National Semiconductor, Atmel,Exar, Agilent, Micron Technology, Mitsubishi, OmniVision, STMicroelectronics, and others.

[0091] Returning to FIG. 3, as the sensor 212 receives light from theobject field of view 220, the sensor 212 provides an output 226 that canbe directed to a local or remote storage such as a memory (not shown)and displayed from the memory via a computer and associated display, forexample, without substantially any intervening digital processing (e.g.,straight bit map from sensor memory to display), if desired. It is notedthat local or remote signal processing of the image data received fromthe sensor 212 can also occur. For example, the output 226 can beconverted to electronic data packets and transmitted to a remote systemover a network for further analysis and/or display. Similarly, theoutput 226 can be stored in a local computer memory before beingtransmitted to a subsequent computing system for further analysis and/ordisplay.

[0092] The scaling (or effective projecting) of pixels 214 provided bythe lens network 216 is determined by a novel k-space configuration ordesign in accordance with an aspect of the present invention. Thek-space design of the lens network 216 promotes predetermined k-spacefrequencies of interest and mitigates frequencies outside thepredetermined frequency band. This has the effect of a band-pass filterof the spatial frequencies within the lens network 216 and notablydefines the imaging system 200 in terms of resolution rather thanmagnification. As will be described below, the resolution of the imagingsystem 200 determined by the k-space design promotes a plurality offeatures in a displayed or stored image, such as having high “EffectiveResolved Magnification” (a figure of merit described in following), withrelated high absolute spatial resolution, large depth of field, largerworking distances, and a unitary Modulation Transfer Function as well asother features.

[0093] In order to determine the k-space frequencies, a pixel size isdetermined or a “pitch” or spacing 228 is determined between adjacentreceptors 214 on the sensor 212. The pixel size (e.g., pixel pitch) cancorrespond to the center-to-center distance of adjacent receptors,indicated at 228, which is about the size or diameter of a singlereceptor when the sensor includes all equally sized pixels. The pitch228 defines the Nyquist “cut-off” frequency band of the sensor 212. Itis this frequency band that is promoted by the k-space design, whereasother frequencies are mitigated. In order to illustrate how scaling isdetermined in the imaging system 200, a point 230 of a desired smallestresolvable spot size is illustrated at the object plane 222, wherein thepoint is derived from resolvable characteristics of the lens network216. The point 230, for example, can represent the smallest resolvableobject determined by optical characteristics of the lens network 216.That is, the lens network is configured to have optical characteristics(e.g., magnification, numerical aperture) so that respective pixels 214are matched or scaled to be within a ratio described below of the sizein the object field of view 220 as the desired minimum resolvable spotsize of the point 230. For purposes of illustration, a scaled receptor232 is depicted in front of the field of view 220 as having a sizedetermined according to the pitch 228 of the sensor 212, which is aboutthe same as the point 230.

[0094] By way of illustration, the lens network 216 is designed toeffectively reduce the size of each given receptor (e.g., pixel) 214 atthe sensor 212 to be within the ratio (e.g., matched in size) of thesize of the point 230, which is typically the minimum spot sizeresolvable by the system 210. It is to be understood and appreciatedthat the point 230 can be selected to a size representing the smallestresolvable object determined by optical characteristics within the lensnetwork 216 as determined by diffraction rules (e.g., diffractionlimited spot size). The lens network 216 thus can be designed toeffectively scale each pixel 214 of the sensor 212 to any size that isequal to or greater than the diffraction limited size. For example, theresolvable spot size can be selected to provide for any desired imageresolution that meets such criteria.

[0095] After the desired resolution (resolvable spot size) is selected,the lens network 216 is designed to provide the magnification to scalethe pixels 214 to the object field of view 220 accordingly. This has theeffect of filling the object field of view 220 with substantially all ofthe receptors of the sensor 212, the respective receptors being suitablyscaled to be similar in size to the point 230, defined by ratiosdescribed below, which corresponds to the desired resolvable spot size.The matching/mapping of sensor characteristics to the desired (e.g.,smallest) resolvable object or point 230 within the object field of view220 defines the imaging system 200 in terms of absolute spatialresolution and enhances the operating performance of the system inaccordance with an aspect of the present invention.

[0096] By way of further illustration, in order to provide unit-mappingaccording to this example, assume that the sensor array 212 provides apixel pitch 228 of about 10 microns. The lens network 216 includes anobjective lens 234 and a secondary lens 236. For example, the objectivelens 234 can be set at infinite conjugate to the secondary lens 236,with the spacing between the objective and secondary lenses beingflexible. The lenses 234 and 236 are related to each other so as toachieve a reduction from sensor space defined at the sensor array 220 toobject space defined at the object plane 222. It is noted thatsubstantially all of the pixels 214 are projected into the object fieldof view 220, which is defined by the objective lens 234. For example,the respective pixels 214 are scaled through the objective lens 234 toabout the dimensions of the desired minimum resolvable spot size. Inthis example, the desired resolution at the image plane 222 is onemicron. Thus, a magnification of ten times is operative to back projecta ten micron pixel to the object plane 222 and reduce it to a size ofone micron.

[0097] The reduction in size of the array 212 and associated pixels 214can be achieved by selecting the transfer lens 236 to have a focallength “D2” (from the array 212 to the transfer lens 236) of about 150millimeters and by selecting the objective lens to have a focal length“D1” (from the objective lens 236 to the object plane 222) of about 15millimeters, for example. In this manner, the pixels 214 are effectivelyreduced in size to about 1 micron per pixel, thus matching the size ofthe of the desired resolvable spot 230 and filling the object field ofview 220 with a “virtually-reduced” array of pixels. It is to beunderstood and appreciated that other arrangements of one or more lensescan be employed to provide the desired scaling.

[0098] In view of the foregoing description, those skilled in the artwill understand and appreciate that the optical media (e.g., lensnetwork 216) can be designed, in accordance with an aspect of thepresent invention, with standard, relatively inexpensive “off-the-shelf”components having a configuration that defines that the object and imagespace are “unit-mapped” or “unit-matched” for substantially all imageand object fields. The lens network 216 and, in particular the objectivelens 234, performs a Fourier transform of an object and an image ink-space (also referred to as “reciprocal-space”). It is this transformthat is operated on for image optimization by the k-space design of thepresent invention.

[0099] A small Blur-circle or Airy disk at the object plane is definedby the design to match the projected pixels in the object plane within acertain ratio (size of projected pixel to size of the Airy disk) andthus the Fourier transforms of pixilated arrays can be matched. Thisimplies that, optically by design, the Airy disk is scaled through thelens network 216 to be about the same size as the receptor or pixelsize. As mentioned above, the lens network 216 is defined so as toconstruct an Intrinsic Spatial Filter (e.g., a k-space filter). Such adesign definition and implementation enables the spectral components ofboth the object and the image in k-space to be about the same orquantized. This also defines that a Modulation Transfer Function (MTF)(the comparison of contrast to spatial resolution) of the sensor can bematched to the MTF of the object Plane in accordance with an aspect ofthe present invention.

[0100] A diffraction limited spot of an image transfer medium is thesmallest resolvable object. The diffraction limited spot size is aparameter of an image transfer medium, such as a lens system. That is,the diffraction limited spot size varies from one lens to another. Thediffraction limited spot is typically determined by the full width halfmaximum of the central peak of the gaussian diffraction spot. At leastabout 85% of the radiation energy exists in the central peak.Preferably, at least about 88% of the radiation energy exists in thecentral peak. Even more preferably, at least about 90% of the radiationenergy exists in the central peak.

[0101] The diffraction limited spot size depends, in part, upon thewavelength of light used to capture an image. Any wavelength of lightcan be employed to form images in accordance with the invention. Whenusing LEDs as an illumination source in the invention, it is possible tomore narrowly provide light for capturing images. In one exemplaryaspect of the invention, when an LED is employed to provideillumination, at least about 75% of the light energy has a wavelengthrange from about 100 nm to about 10,000 nm. In another exemplary aspectof the invention, at least about 75% of the light energy has awavelength range from about 100 nm to about 400 nm. In yet anotherexemplary aspect of the invention, at least about 75% of the lightenergy has a wavelength range from about 400 nm to about 700 nm. Instill yet another exemplary aspect of the invention, at least about 75%of the light energy has a wavelength range from about 700 nm to about2,000 nm. In another exemplary aspect of the invention, at least about75% of the light energy has a wavelength range from about 250 nm toabout 500 nm. In another exemplary aspect of the invention, at leastabout 75% of the light energy has a wavelength range from about 500 nmto about 1,200 nm. In yet another exemplary aspect of the invention, atleast about 75% of the light energy has a wavelength range from about350 nm to about 1,000 nm.

[0102] A diffraction spot exists on an object side of the image transfermedium and on an image side of the image transfer medium. Generallyspeaking, when referring herein to diffraction limited spot ordiffraction limited spot size, diffraction spot or diffraction spotsize, it is the diffraction limited spot on the object side and in theobject plane unless specified otherwise.

[0103] The diffraction limited spot shape is commonly a circle. However,the diffraction limited spot is determined by the physical dimensionsand/or properties of the lens. The diffraction limited spot can have anyshape so long as it retains its characteristic function. Additionalshapes of diffraction spots include ovals, ellipses, hexagons, octagons,and other polygons, and the like. The size of the diffraction spottypically varies from image transfer medium to image transfer medium.For example, size of the diffraction spot typically varies from lens tolens.

[0104] There are a number of ways in which to measure diffractionlimited spot size. Typically, when not specified otherwise, diffractionspot size is represented by diameter, which the cross-section throughthe centerpoint of a circle. Diffraction limited spot size canalternatively be represented by area. In the case of a lens train,diffraction spot size is determined based on the combination of lenses.In the case of an ellipse, the diameter refers to a line through themiddle, perpendicular to the line that includes the two foci.

[0105] In one aspect of the invention, the diffraction spot (in theobject plane) has a diameter of about 0.01 microns or more and about 20microns or less. In another aspect of the invention, the diffractionspot has a diameter of about 0.05 microns or more and about 15 micronsor less. In yet another aspect of the invention, the diffraction spothas a diameter of about 0.1 microns or more and about 10 microns orless. In still yet another aspect of the invention, the diffraction spothas a diameter of about 0.5 microns or more and about 5 microns or less.

[0106] In one aspect of the invention, the diffraction spot size isdiffraction spot area that is about 0.0003 microns² or more and about600 microns² or less. In another aspect of the invention, thediffraction spot size is diffraction spot area that is about 0.001microns² or more and about 200 microns² or less. In yet another aspectof the invention, the diffraction spot size is diffraction spot areathat is about 0.01 microns² or more and about 100 microns² or less. Instill yet another aspect of the invention, the diffraction spot size isdiffraction spot area that is about 0.1 microns or more and about 50microns² or less.

[0107] In another aspect of the invention, the image transfer medium hasa diffraction limited spot in an image plane having a diameter of about0.1 microns or more and about 20 microns or less, and/or an area that isabout 0.01 microns or more and about 600 microns² or less. In yetanother aspect of the invention, the image transfer medium has adiffraction limited spot in an image plane having a diameter of about0.25 microns or more and about 15 microns or less, and/or an area thatis about 0.1 microns² or more and about 200 microns² or less.

[0108] Examples of commercially available image transfer media, such aslenses, are those made by Bausch & Lomb, Canon, edmund Optics, Fujinon,Kahles, Kowa, Leica, Minolta, Minox, Meiji, Melles Griot, Mitutoyo,Nikon, Olympus, Pentax, Prior, Steiner, Swarovski, Swift, Unitron, Wild,Zeiss, and others. Any type of lens may be employed, so long as thediffraction limited spot in the object plane is matched with the pixelsize of the sensor. Examples of lenses that may be employed in the imagetransfer system include Plan_Neofluar, Plan Fluotar, Planapochromat,Plan, Achroplan, Epiplans, Achromat, Planachromats, Semiapochromatic,Apochromatic, Planapochromat, and the like.

[0109] As illustrated in FIG. 3, k-space is defined as the regionbetween the objective lens 234 and the secondary lens 236. It is to beappreciated that substantially any optical media, lens type and/or lenscombination that reduces, maps and/or projects the sensor array 212 tothe object field of view 220 in accordance with unit or k-space mappingas described herein is within the scope of the present invention.

[0110] To illustrate the novelty of the exemplary lens/sensorcombination depicted in FIG. 3, it is noted that conventional objectivelenses, sized according to conventional geometric paraxial raytechniques, are generally sized according to the magnification, NumericAperture, focal length and other parameters provided by the objective.Thus, the objective lens would be sized with a greater focal length thansubsequent lenses that approach or are closer to the sensor (or eyepiecein conventional microscope) in order to provide magnification of smallobjects. This can result in magnification of the small objects at theobject plane being projected as a magnified image of the objects across“portions” of the sensor and results in known detail blur (e.g.,Rayleigh diffraction and other limitations in the optics), emptymagnification problems, and Nyquist aliasing among other problems at thesensor. The k-space design of the present invention operates in analternative manner to conventional geometrical paraxial ray designprinciples. That is, the objective lens 234 and the secondary lens 236operate to provide a reduction in size of the sensor array 212 to theobject field of view 220, as demonstrated by the relationship of thelenses.

[0111] An illumination source 240 can be provided with the presentinvention in order that photons from that source can be transmittedthrough and/or reflected from objects in the field of view 234 to enableactivation of the receptors in the sensor 212. It is noted that thepresent invention can potentially be employed without an illuminationsource 240 if potential self-luminous objects (e.g., objects orspecimens with emissive characteristics as previously described) emitenough radiation to activate the sensor 212. Substantially anyillumination source 240 can be applied including coherent andnon-coherent sources, visible and non-visible wavelengths. However, fornon-visible wavelength sources, the sensor 212 would also be suitablyadapted. For example, for an infrared or ultraviolet source, an infraredor ultraviolet sensor 212 would be employed, respectively. Othersuitable illumination sources 240 can include wavelength-specificlighting, broad-band lighting, continuous lighting, strobed lighting,Kohler illumination, Abbe illumination, phase-contrast illumination,darkfield illumination, brightfield illumination, Epi illumination, andthe like. Transmissive or reflective (e.g., specular and diffuse)lighting techniques can also be applied.

[0112]FIG. 4 illustrates a graph 300 of mapping characteristics andcomparison between projected pixel size on the X-axis anddiffraction-limited spot resolution size “R” on the Y-axis. An apex 310of the graph 300 corresponds to unit mapping between projected pixelsize and the diffraction limited spot size, which represents an optimumrelationship between a lens network and a sensor in accordance with thepresent invention.

[0113] It is to be appreciated that the objective lens 234 (FIG. 3)should generally not be selected such that the diffraction-limited size“R” of the smallest resolvable objects are substantially smaller than aprojected pixel size. If so, “economic waste” can occur wherein moreprecise information is lost (e.g., selecting an object lens moreexpensive than required, such as having a higher numerical aperture).This is illustrated to the right of a dividing line 320 at reference 330depicting a projected pixel 340 larger that two smaller diffractionspots 350. In contrast, where an objective is selected withdiffraction-limited performance larger than the projected pixel size,blurring and empty magnification can occur. This is illustrated to theleft of line 320 at reference numeral 360, wherein a projected pixel 370is substantially smaller than a diffraction-limited object 380. It is tobe appreciated, however, that even if substantially one-to-onecorrespondence is not achieved between projected pixel size and thediffraction-limited spot, a system can be configured with less thanoptimum matching (e.g., 0.1%, 1%, 2%, 5%, 20%, 95% down from the apex310 on the graph 300 to the left or right of the line 320) and stillprovide suitable performance in accordance with an aspect of the presentinvention. Thus, less than optimal matching is intended to fall withinthe spirit and the scope of present invention.

[0114] It is further to be appreciated that the diameter of the lensesin the system as illustrated in FIG. 3, for example, should be sizedsuch that when a Fourier Transform is performed from object space tosensor space, spatial frequencies of interest that are in the band passregion described above (e.g., frequencies utilized to define the sizeand shape of a pixel) are substantially not attenuated. This generallyimplies that larger diameter lenses (e.g., about 10 to 100 millimeters)should be selected to mitigate attenuation of the spatial frequencies ofinterest.

[0115] The projected pixel size of the sensor in the object plane andthe diffraction limited spot size in the object plane of the imagetransfer medium are substantially matched or unit-mapped to provide atleast one of improved absolute spatial resolution, improved depth offield, improved contrast, and improved field of view over digital imagesmanufactured by a system where the pixel size of the sensor and thediffraction limited spot size in the object plane of the image transfermedium are not substantially matched or unit-mapped.

[0116] Matched or unit-mapped projected pixels and diffraction limitedspots means that both the projected pixel area and diffraction limitedspot size area in the object plane are about 0.0003 microns² or more andabout 600 microns² or less. Alternatively or additionally, both theprojected pixel projected pitch, projected pixel width, projected pixellength, or projected pixel diameter in the object plane and diffractionlimited spot diameter in the object plane are about 0.01 microns or moreand about 20 microns or less. The projected pixel size and thediffraction spot size determined by any measurement are suitably matchedor unit-mapped to provide resolved images with generous field of viewand depth of field.

[0117] In one aspect of the invention, the ratio of the projected pixelsize to the diffraction spot size, both in the object plane anddetermined by pitch, length, width, or diameter, is between 1:2 and 2:1.In another aspect of the invention, the ratio of the projected pixelsize to the diffraction spot size, both in the object plane anddetermined by pitch, length, width, or diameter, is from about 1:1.9 toabout 1.9:1. In another aspect of the invention, the ratio of theprojected pixel size to the diffraction spot size, both in the objectplane and determined by pitch, length, width, or diameter, is from about1:1.7 to about 1.7:1. In another aspect of the invention, the ratio ofthe projected pixel size to the diffraction spot size, both in theobject plane and determined by pitch, length, width, or diameter, isfrom about 1:1.5 to about 1.5:1. In another aspect of the invention, theratio of the projected pixel size to the diffraction spot size, both inthe object plane and determined by pitch, length, width, or diameter, isfrom about 1:1.4 to about 1.4:1. In another aspect of the invention, theratio of the projected pixel size to the diffraction spot size, both inthe object plane and determined by pitch, length, width, or diameter, isfrom about 1:1.3 to about 1.3:1. In another aspect of the invention, theratio of the projected pixel size to the diffraction spot size, both inthe object plane and determined by pitch, length, width, or diameter, isfrom about 1:1.2 to about 1.2:1. In another aspect of the invention, theratio of the projected pixel size to the diffraction spot size, both inthe object plane and determined by pitch, length, width, or diameter, isfrom about 1:1.1 to about 1.1:1.

[0118] In one aspect of the invention, the ratio of the projected pixelsize to the diffraction spot size, both in the object plane anddetermined by area, is from about 5:1 to about 1:12. In another aspectof the invention, the ratio of the projected pixel size to thediffraction spot size, both in the object plane and determined by area,is from about 4:1 to about 1:10. In yet another aspect of the invention,the ratio of the projected pixel size to the diffraction spot size, bothin the object plane and determined by area, is from about 3.5:1 to about1:8. In still yet another aspect of the invention, the ratio of theprojected pixel size to the diffraction spot size, both in the objectplane and determined by area, is from about 3:1 to about 1:6. In anotheraspect of the invention, the ratio of the projected pixel size to thediffraction spot size, both in the object plane and determined by area,is from about 2.5:1 to about 1:5. In another aspect of the invention,the ratio of the projected pixel size to the diffraction spot size, bothin the object plane and determined by area, is from about 2:1 to about1:4. In another aspect of the invention, the ratio of the projectedpixel size to the diffraction spot size, both in the object plane anddetermined by area, is from about 1.5:1 to about 1:3. In another aspectof the invention, the ratio of the projected pixel size to thediffraction spot size, both in the object plane and determined by area,is from about 1.25:1 to about 1:2. In another aspect of the invention,the ratio of the projected pixel size to the diffraction spot size, bothin the object plane and determined by area, is from about 1.1:1 to about1:1.5.

[0119] Although not critical to the invention, in one aspect of theinvention, the ratio of the pixel size to the diffraction limited spotin the image plane, both determined by pitch, length, width, ordiameter, is from about 1:1.5 to about 1.5:1. In another aspect of theinvention, the ratio of the pixel size to the diffraction limited spotin the image plane, both determined by pitch, length, width, ordiameter, is from about 1:1.25 to about 1.25:1. In another aspect of theinvention, the ratio of the pixel size to the diffraction limited spotin the image plane, both determined by pitch, length, width, ordiameter, is from about 1:1.1 to about 1.1:1.

[0120] Referring now to FIG. 5, a Modulation Transfer function 400 isillustrated in accordance with the present invention. On a Y-axis,modulation percentage from 0 to 100% is illustrated defining percentageof contrast between black and white. On an X-axis, Absolution SpatialResolution is illustrated in terms of microns of separation. A line 410illustrates that modulation percentage remains substantially constant atabout 100% over varying degrees of spatial resolution. Thus, theModulation Transfer Function is about 1 for the present invention up toabout a limit imposed by the signal to noise sensitivity of the sensor.For illustrative purposes, a conventional optics design ModulationTransfer Function is illustrated by line 420 which may be an exponentialcurve with generally asymptotic limits characterized by generallydecreasing spatial resolution with decreasing modulation percentage(contrast).

[0121]FIG. 6 illustrates a quantifiable Figure of Merit (FOM) for thepresent invention defined as dependent on two primary factors: AbsoluteSpatial Resolution (R_(A), in microns), depicted on the Y axis and theField Of View (F, in microns) depicted on the X axis of a graph 500. Areasonable FOM called “Spatial Field Number” (S), can be expressed asthe ratio of these two previous quantities, with higher values of Sbeing desirable for imaging as follows:

S=F/R _(A)

[0122] A line 510 illustrates that the FOM remains substantiallyconstant across the field of view and over different values of absolutespatial resolution which is an enhancement over conventional systems.

[0123]FIGS. 7, 8, 14, 15, 16, and 20 illustrate methodologies tofacilitate imaging performance in accordance with the present invention.While, for purposes of simplicity of explanation, the methodologies maybe shown and described as a series of acts, it is to be understood andappreciated that the present invention is not limited by the order ofacts, as some acts may, in accordance with the present invention, occurin different orders and/or concurrently with other acts from that shownand described herein. For example, those skilled in the art willunderstand and appreciate that a methodology could alternatively berepresented as a series of interrelated states or events, such as in astate diagram. Moreover, not all illustrated acts may be required toimplement a methodology in accordance with the present invention.

[0124] Turning now to FIG. 7 and proceeding to 610, lenses are selectedhaving diffraction-limited characteristics at about the same size of apixel in order to provide unit-mapping and optimization of the k-spacedesign. At 614, lens characteristics are also selected to mitigatereduction of spatial frequencies within k-space. As described above,this generally implies that larger diameter optics are selected in orderto mitigate attenuation of desired k-space frequencies of interest. At618, a lens configuration is selected such that pixels, having a pitch“P”, at the image plane defined by the position of a sensor are scaledaccording to the pitch to an object field of view at about the size of adiffraction-limited spot (e.g., unit-mapped) within the object field ofview. At 622, an image is generated by outputting data from a sensor forreal-time monitoring and/or storing the data in memory for directdisplay to a computer display and/or subsequent local or remote imageprocessing and/or analysis within the memory.

[0125]FIG. 8 illustrates a methodology that can be employed to design anoptical/imaging system in accordance with an aspect of the presentinvention. The methodology begins at 700 in which a suitable sensorarray is chosen for the system. The sensor array includes a matrix ofreceptor pixels having a known pitch size, usually defined by themanufacturer. The sensor can be substantially any shape (e.g.,rectangular, circular, square, triangular, and so forth). By way ofillustration, assume that a sensor of 640×480 pixels having a pitch sizeof 10 μm is chosen. It is to be understood and appreciated that anoptical system can be designed for any type and/or size of sensor arrayin accordance with an aspect of the present invention.

[0126] Next at 710, an image resolution is defined. The image resolutioncorresponds to the smallest desired resolvable spot size at the imageplane. The image resolution can be defined based on the application(s)for which the optical system is being designed, such as any resolutionthat is greater than or equal to a smallest diffraction limited size.Thus, it is to be appreciated that resolution becomes a selectabledesign parameter that can be tailored to provide desired imageresolution for virtually any type of application. In contrast, mostconventional systems tend to limit resolution according to Rayleighdiffraction, which provides that intrinsic spatial resolution of thelenses cannot exceed limits of diffraction for a given wavelength.

[0127] After selecting a desired resolution (710), a suitable amount ofmagnification is determined at 720 to achieve such resolution. Forexample, the magnification is functionally related to the pixel pitch ofthe sensor array and the smallest resolvable spot size. Themagnification (M) can be expressed as follows: $\begin{matrix}{M = \frac{x}{y}} & {{Eq}.\quad 1}\end{matrix}$

[0128] wherein: x is the pixel size such as pixel pitch of the sensorarray; and

[0129] y is the desired image resolution (minimum spot size).

[0130] So, for the above example where the pixel pitch is 10 μm andassuming a desired image resolution of 1 μm, Eq. 1 provides an opticalsystem of power ten. That is, the lens system is configured toback-project each 10 82 m pixel to the object plane and reducerespective pixels to the resolvable spot size of 1 micron.

[0131] The methodology of FIG. 8 also includes a determination of aNumerical Aperture at 730. The Numerical Aperture (NA) is determinedaccording to well-established diffraction rules that relate NA of theobjective lens to the minimum resolvable spot size determined at 710 forthe optical system. By way of example, the calculation of NA can bebased on the following equation: $\begin{matrix}{{NA} = \frac{0.5 \times \lambda}{y}} & {{Eq}.\quad 2}\end{matrix}$

[0132] where: λ is the wavelength of light being used in the opticalsystem; and

[0133] y is the minimum spot size (e.g., determined at 710).

[0134] Continuing with the example in which the optical system has aresolved spot size of y=1 micron, and assuming a wavelength of about 500nm (e.g., green light), a NA=0.25 satisfies Eq. 2. It is noted thatrelatively inexpensive commercially available objectives of power 10provide numerical apertures of 0.25.

[0135] It is to be understood and appreciated that the relationshipbetween NA, wavelength and resolution represented by Eq. 2 can beexpressed in different ways according to various factors that accountfor the behavior of objectives and condensers. Thus, the determinationat 730, in accordance with an aspect of the present invention, is notlimited to any particular equation but instead simply obeys knowngeneral physical laws in which NA is functionally related to thewavelength and resolution. After the lens parameters have been designedaccording to the selected sensor (700), the corresponding opticalcomponents can be arranged to provide an optical system (740) inaccordance with an aspect of the present invention.

[0136] Assume, for purposes of illustration, that the example opticalsystem created according to the methodology of FIG. 8 is to be employedfor microscopic-digital imaging. By way of comparison, in classicalmicroscopy, in order to image and resolve structures of a sizeapproaching 1 micron (and below), magnifications of many hundredsusually are required. The basic reason for this is that such opticsconventionally have been designed for the situation when the sensor ofchoice is the human eye. In contrast, the methodology of FIG. 8 designsthe optical system in view of the sensor, which affords significantperformance increases at reduced cost.

[0137] In the k-space design methodology, according to an aspect of thepresent invention, the optical system is designed around a discretesensor that has known fixed dimensions. As a result, the methodology canprovide a far more straight-forward, robust, and inexpensive opticalsystem design approach to “back-project” the sensor size onto the objectplane and calculate a magnification factor. A second part of themethodology facilitates that the optics that provide the magnificationhave a sufficient NA to optically resolve a spot of similar dimensionsas the back-projected pixel. Advantageously, an optical system designedin accordance with an aspect of the present invention can utilize customand/or off-the-shelf components. Thus, for this example, inexpensiveoptics can be employed in accordance with an aspect of the presentinvention to obtain suitable results, but well-corrected microscopeoptics are relatively inexpensive. If custom-designed optics areutilized, in accordance with an aspect of the present invention, thenthe range of permissible magnifications and numerical apertures becomessubstantial, and some performance gains can be realized over the use ofoff-the-shelf optical components.

[0138] In view of the concepts described above in relation to FIGS. 1-8,a plurality of related imaging applications can be enabled and enhancedby the present invention. For example, these applications can includebut are not limited to imaging, control, inspection, microscopy and/orother automated analysis such as:

[0139] (1) Bio-medical analysis (e.g., cell colony counting, histology,frozen sections, cellular cytology, Meachanical, Laser orradiation-based, and other Micro-dissection, Haematology, pathology,oncology, fluorescence, interference, phase and many other clinicalmicroscopy applications);

[0140] (2) Particle Sizing Applications (e.g., Pharmaceuticalmanufacturers, paint manufacturers, cosmetics manufacturers, foodprocess engineering, and others);

[0141] (3) Air quality monitoring and airborne particulate measurement(e.g., clean room certification, environmental certification, and soforth);

[0142] (4) Optical defect analysis, and other requirements for highresolution microscopic inspection of both transmissive and opaquematerials (as in metallurgy, automated semiconductor inspection andanalysis, automated vision systems, 3-D imaging and so forth); and

[0143] (5) Imaging technologies such as cameras, copiers, FAX machinesand medical systems as well as other technologies/applications which aredescribed in more detail below.

[0144]FIGS. 9, 10, 11, 12, and 13 illustrate possible example systemsthat can be constructed employing the concepts previously describedabove in relation to FIGS. 1-8. FIG. 9 is a flow diagram of light pathsin an imaging system 800 adapted in accordance with the presentinvention.

[0145] The system 800 employs a light source 804 emitting illuminatinglight that is received by a light condenser 808. Output from the lightcondenser 808 is directed to a microscope condenser 816 (such outputfrom 808 also can be directed by a fold mirror, or other component orcomponents that redirect the optical path, as shown at 812) thatprojects illuminating light onto a slide stage 820, wherein an object(not shown, positioned on top of, or within the slide stage and theField Volume Depth at the object plane) can be imaged in accordance withthe present invention. The slide stage 820 can be automaticallypositioned (and/or manually) via a computer 824 and associated slidefeed 828 in order to image one or more objects in a field of viewdefined by an objective lens 832. It is noted that the objective lens832 and/or other components depicted in the system 800 may be adjustedmanually and/or automatically via the computer 824 and associatedcontrols (not shown) (e.g., servo motors, tube slides, linear and/orrotary position encoders, optical, magnetic, electronic, or otherfeedback mechanisms, control software, and so forth) to achievedifferent and/or desired image characteristics (e.g., magnification,focus, which objects appear in field of view, depth of field and soforth).

[0146] Light output from the objective lens 832 can be directed throughan optional beam splitter 840, wherein the beam splitter 840 isoperative with an alternative epi-illumination section 842 (to lightobjects from above slide stage 820) including light shaping optics 844and associated light source 848. Light passing through the beam splitter840 is received by an image forming lens 850. Output from the imageforming lens 850 is directed to a CCD or other imaging sensor or device854. It is shown that the output of 850 can also be directed to device854 via a fold mirror 860, or other component or components thatredirect the optical path as desired. The CCD or other imaging sensor ordevice 854 converts the light received from the object to digitalinformation for transmission to the computer 824, wherein the objectimage can be displayed to a user in real-time and/or stored in memory at864. As noted above, the digital information defining the image capturedby the CCD or other imaging sensor or device 854 can be routed asbit-map information to the display/memory 864 by the computer 824. It isto be appreciated that “display” can be any of, but not limited to anytype of computer monitor, CRT, LCD, TV, organic light emitting devicedisplay (OLED), or other semi-conductor image display device; miniatureor any other type large or small-scale display projector, head-mount,flexible, monocular, binocular, or projection display, retinal display,Head-Up display, and others of the like. If desired, image processingsuch as automatic comparisons with predetermined samples or images canbe performed to determine an identity of and/or analyze the object underexamination. This can also include employment of substantially any typeof image processing technology or software that can be applied to thecaptured image data within the memory 864.

[0147]FIG. 10 is a system 900 depicting an exemplary modular approach toimaging design in accordance with an aspect of the present invention.The system 900 can be based on a sensor array 910 (e.g., provided inoff-the-shelf camera) with a pixel pitch of approximately 8 microns (orother dimension), for example, wherein array sizes can vary from 640×480to 1280×1024 (or other dimensions as noted above as currently extantproducts or any other such arrays as might become available.). Thesystem 900 includes a modular design wherein a respective module issubstantially isolated from another module, thus, mitigating alignmenttolerances.

[0148] The modules can include:

[0149] a camera/sensor module, 914 including an image-forming lens 916and/or fold mirror 918;

[0150] an epi-illumination module 920 for insertion into a k-spaceregion 922;

[0151] a sample holding and presentation module 924;

[0152] a light-shaping module 930 including a condenser 934; and

[0153] a sub-stage lighting module 940.

[0154] It is noted that the system 900 can advantageously employcommercially-available components such as for example:

[0155] condenser optics 934 (NA<=1) for the light presentation;

[0156] (e.g., Olympus U-SC-2)

[0157] standard plan/achromatic objective lenses or any other availableor custom optical design and characteristic transmissive, reflective, orother optical path directive components 944 of power and numericalaperture e.g.,: (4×, 0.10), (10×, 0.25), (20×, 0.40), (40×, 0.65)selected to satisfy the desired characteristic that for a givenmagnification, the projected pixel-pitch at the object plane is similarin dimensions to the diffraction-limited resolved spot of the optics.

[0158] (e.g., Olympus 1-UB222, 1-UB223, 1-UB225, 1-UB227)

[0159] The system 900 utilizes an infinity-space (k-space) between theobjective lens 944 and the image-forming lens 916 in order to facilitatethe insertion of auxiliary and/or additional optical components,modules, filters, and so forth in the k-space region at 922 such as forexample, when the image-forming lens 916 is adapted as an f=150 mmachromatic triplet. Furthermore, an infinity-space (k-space) between theobjective lens 944 and the image-forming lens 916 can be provided inorder to facilitate the injection of object illumination light (via alight-forming path) into an optical path for epi-illumination. Forexample, the light-forming path for epi-illumination can include:

[0160] a light source 950 such as an LED driven from acurrent-stabilised supply;

[0161] (e.g., HP HLMP-CW30)

[0162] a transmission hologram for source homogenisation and theimposition of a spatial virtual-source at 950;

[0163] (e.g., POC light shaping diffuser polyester film 30-degree FWHM)

[0164] a variable aperture at 960 to restrict the NA of the source 950to that of the imaging optics, thereby mitigating the effect ofscattered light entering the image-forming optical path;

[0165] (e.g., Thorlabs iris diaphragm SM1D12 0.5-12.0 mm aperture)

[0166] a collection lens at 960 employed to maximize the light gatheredfrom the virtual source 950, and to match the k-space characteristics ofthe source to that of the imaging optics; and

[0167] (e.g., f=50 mm aspheric lens, f=50 mm achromatic doublet)

[0168] a partially-reflective beam splitter 964 employed to form acoaxial light path and image path. For example, the optic 964 provides a50% reflectivity on a first surface (at an inclination of 45 degrees),and is broadband antireflection coated on a second surface.

[0169] The sub-stage lighting module 940 is provided by an arrangementthat is substantially similar to that of the epi-illumination describedabove for example:

[0170] a light source 970 (an LED driven from a current-stabilisedsupply);

[0171] (e.g., HP HLMP-CW30)

[0172] a transmission hologram (associated with light source 970) forthe purposes of source homogenisation and the imposition of a spatialvirtual-source;

[0173] (e.g., POC light shaping diffuser polyester film 30-degree FWHM)

[0174] a collection lens 974 employed to maximize the light gatheredfrom the virtual source 970, and to match the k-space characteristics ofthe source to that of the imaging optics;

[0175] (e.g., f=50 mm aspheric lens, f=50 mm achromatic doublet)

[0176] a variable aperture 980 to restrict the NA of the source 970 tothat of the imaging optics, thereby mitigating the effect of scatteredlight entering the image-forming optical path;

[0177] (e.g., Thorlabs iris diaphragm SM1D12 0.5-12.0 mm aperture)

[0178] a mirror 988 utilized to turn the optical path through 90 degreesand provide fine-adjustment in order to accurately align the opticalmodules, though it will be appreciated that the described optical pathlength “turn” is not required for such alignment but facilitates suchalignment by mitigating mechanical and tolerancing errors; and

[0179] a relay lens (not shown) employed to accurately position theimage of the variable aperture 980 onto the object plane (at slide 990),thereby, along with suitable placement of a holographic diffuser, thus,achieving Kohler illumination.

[0180] (e.g., f=100 mm simple piano-convex lens).

[0181] As described above, a computer 994 and associated display/memory998 is provided to display in real-time and/or store/process digitalimage data captured in accordance with the present invention.

[0182]FIG. 11 illustrates a system 1000 in accordance with an aspect ofthe present invention. In this aspect, a sub-stage lighting module 1010(e.g., Kohler, Abbe) can project light through a transmissive slide 1020(object under examination not shown), wherein an achromatic objectivelens 1030 receives light from the slide and directs the light to animage capture module at 1040. It is noted that the achromatic objectivelens 1030 and/or slide 1020 can be manually and/or automaticallycontrolled to position the object(s) under examination and/or positionthe objective lens.

[0183]FIG. 12 illustrates a system 1100 in accordance with an aspect ofthe present invention. In this aspect, a top-stage or epi-illuminationlighting module 1110 can project light to illuminate transmissive oropaque objects on an appropriately transmissive or opaque slide orcarrier or suitable mounting substrate 1120 (object under examinationnot shown), wherein an objective lens 1130 (can be compound lens deviceor other type) receives light from the slide and directs the light to animage capture module at 1140. As noted above, the objective lens 1130and/or slide 1120 can be manually and/or automatically controlled toposition the object(s) under examination and/or position the objectivelens. FIG. 13 depicts a system 1200 that is similar to the system 1000in FIG. 11 except that a compound objective lens 1210 is employed inplace of an achromatic objective lens.

[0184] The imaging systems and processes described above in connectionwith FIGS. 1-13 may thus be employed to capture/process an image of asample, wherein the imaging systems are coupled to a processor orcomputer that reads the image generated by the imaging systems andcompares the image to a variety of images in an on-board data store inany number of current memory technologies.

[0185] For example, the computer can include an analysis component toperform the comparison. Some of the many algorithms employed in imageprocessing include, but are not limited to convolution (on which manyothers are based), FFT, DCT, thinning (or skeletonization), edgedetection and contrast enhancement. These are usually implemented insoftware but may also use special purpose hardware for speed. FFT (fastFourier transform) is an algorithm for computing the Fourier transformof a set of discrete data values. Given a finite set of data points, forexample, a periodic sampling taken from a real-world signal, the FFTexpresses the data in terms of its component frequencies. It alsoaddresses the essentially identical inverse concerns of reconstructing asignal from the frequency data. DCT (discrete cosine transform) is atechnique for expressing a waveform as a weighted sum of cosines. Thereare a various extant programming languages designed for image processingwhich include but are not limited to those such as IDL, Image Pro,Matlab, and many others. There are also no specific limits to thespecial and custom image processing algorithms that may be written toperform functional image manipulations and analyses.

[0186] The k-space design of the present invention also allows fordirect optical correlation of the Fourier Frequency informationcontained in the image with stored information to perform real-timeoptically correlated image processed analyses of a given sample object.

[0187]FIG. 14 illustrates a particle sizing application 1300 that can beemployed with the systems and processes previously described. Particlesizing can include real-time, closed/open loop monitoring, manufacturingwith, and control of particles in view of automatically determinedparticles sizes in accordance with the k-space design conceptspreviously described. This can include automated analysis and detectiontechniques for various particles having similar or different sizes (ndifferent sizes, n being an integer) and particle identification ofm-shaped/dimensioned particles, m being an integer). In one aspect ofthe present invention, desired particle size detection and analysis canbe achieved via a direct measurement approach. This implies that theabsolute spatial resolution per pixel relates directly (or substantiallythereto) in units of linear measure to the imaged particles withoutsubstantial account of the particle medium and associated particledistribution. Direct measurement generally does not create a model butrather provides a metrology and morphology of the imaged particles inany given sample. This mitigates processing of modelling algorithms,statistical algorithms, and other modelling limitations presented bycurrent technology. Thus, an issue becomes one of sample handling andform that enhances the accuracy and precision of measurements since theparticle data is directly imaged and measured rather than modelled, ifdesired.

[0188] Proceeding to 1310 of the particle sizing application 1300,particle size image parameters are determined. For example, basic devicedesign can be configured for imaging at desired Absolute SpatialResolution per pixel and Effective Resolved Magnification as previouslydescribed. These parameters determine field of view (FOV), depth offield (DOF), and working distance (WD), for example. Real-timemeasurement can be achieved by either synchronous or asynchronousimaging of a medium at selected timing intervals, in real-time at commonvideo rates, and/or at image capture rates as desired. Real-time imagingcan also be achieved by capturing images at selected times forsubsequent image processing. Asynchronous imaging can be achieved bycapturing images at selected times by pulsing an instrument illuminationat selected times and duty cycles for subsequent image processing.

[0189] At 1320, a sample introduction process is selected for automated(or manual) analysis. Samples can be introduced into an imaging deviceadapted in accordance with the present invention in any of the following(but not limited to) imaging processes:

[0190] 1) All previously described methods and transmissive media aswell as:

[0191] 2) Individual manual samples in cuvettes, slides, and/ortransmissive medium.

[0192] 3) Continuous flow of particles in stream of gas or liquid, forexample.

[0193] 4) With an imaging device configured for epi-Illumination orother suitable reflective illumination imaging, samples may be opaqueand presented on an appropriately transmissive or opaque “carrier”(automated and/or manual) without substantial regard to the materialanalyzed.

[0194] At 1330, a process control and/or monitoring system isconfigured. Real-time, closed loop and/or open loop monitoring,manufacturing with (e.g., closing loop around particle size), andcontrol of processes by direct measurement of particle characteristics(e.g., size, shape, morphology, cross section, distribution, density,packing fraction, and other parameters can be automatically determined).It is to be appreciated that although direct measurement techniques areperformed on a given particle sample, that automated algorithms and/orprocessing can also be applied to the imaged sample if desired.Moreover, a direct measurement-based particle characterization devicecan be installed at substantially any given point in a manufacturingprocess to monitor and communicate particle characteristics for processcontrol, quality control, and so forth by direct measurement.

[0195] At 1340, a plurality of different sample types can be selectedfor analysis. For example, particle samples in any of the aforementionedforms can be introduced in continuous flow, periodic, and/orasynchronous processes for direct measurement in a device as part of aprocess closed-feedback-loop system to control, record, and/orcommunicate particle characteristics of a given sample type (can alsoinclude open loop techniques if desired). Asynchronous and/orsynchronous techniques can be employed (the first defines imaging with atriggering signal sent by an event, or trigger signal initiated by anevent or object generating a trigger signal to initiate imaging, thesecond defines imaging with a timing signal sent to trigger illuminationindependent of object location or presence).

[0196] Asynchronous and/or synchronous imaging can be achieved bypulsing an illumination source to coincide with the desired image fieldwith substantially any particle flow rate. This can be controlled by acomputer, for example, and/or by a “trigger” mechanism, eithermechanical, optical, and/or electronic, to “flash” solid stateillumination on and off with a given duty cycle so that the image sensorcaptures, displays and records the image for processing and analysis.This provides a straight-forward process of illuminating and imaginggiven that it effectively can be timed to “stop the action”—or rather,“freeze” the motion of the flowing particles in the medium. In addition,this enables that a sample within the image field to capture particleswithin the field for subsequent image processing and analysis.

[0197] It is to be appreciated that other adaptations and/or definitionsfor analyzing particles or materials can be provided. Rather than asynchronous vs. asynchronous configuration, other imaging aspects caninclude “continuous imaging” and/or “image-on-demand” techniques.Continuous imaging is generally employed with static objects andsteady-state lighting, and image-on-demand for stop-flow techniques(e.g., moving particles/objects, Brownian motion, and so forth).Stop-flow imaging can be achieved by strobing a light source for a shorttime, or by shuttering a camera rapidly, for example, yielding severalpossibilities:

[0198] 1. Strobed illumination+long exposure camera.

[0199] 2. Continuous illumination+short exposure (shuttered) camera.

[0200] 3. Strobed illumination+synchronised shuttered camera.

[0201] As can be appreciated, the above examples can be made synchronousby reference to a suitable time base, or made asynchronous by demandingan image at an arbitrary time interval.

[0202] Real-time (or substantially real time), closed loop and/or openloop monitoring, manufacturing with, and control of processes byk-space-based, direct measurement of particle characterization at 1340is applicable to a broad range of processes including (but not limitedto): Ceramics, metal powders, pharmaceuticals, cement, minerals, ores,coatings, adhesives, pigments, dyes, carbon black, filter materials,explosives, food preparations, health & cosmetic emulsions, polymers,plastics, micelles, beverages—and many more particle-based substancesrequiring process manufacturing, monitoring and control.

[0203] Other applications include but are not limited to:

[0204] Instrument calibration and standards;

[0205] Industrial-hygiene research;

[0206] Materials research;

[0207] Energy and combustion studies;

[0208] Diesel—and gasoline-engine emissions measurements;

[0209] Industrial emissions sampling;

[0210] Basic aerosol research;

[0211] Environmental studies;

[0212] Bio-aerosol detection;

[0213] Including but not limited to biologic agent or contaminant suchas spores, bacteria fungi, etc.

[0214] Pharmaceutical research;

[0215] Health and agricultural experiments;

[0216] Clean-Room Monitoring;

[0217] Inhalation toxicology; and/or

[0218] Filter testing.

[0219] At 1350, software and/or hardware based computerized imageprocessing/analysis can occur. Images from a device adapted inaccordance with the present invention can be processed in accordancewith substantially any hardware and/or software process. Software-basedimage processing can be achieved by custom software and/or commerciallyavailable software since the image file formats are digital formats(e.g., bit maps, TIFF, JPEG, and so forth or any other digital imagefile format (or combinations thereof) of captured particles).

[0220] Analysis, characterization, and so forth can also be provided bythe following: For example, analyses can be metrologic (directmeasurement based), correlative, and/or comparative (database) based.Correlative and/or comparative analyses can include comparisons to adatabase of (but not limited to) complete/partial visual image data,and/or component image data (e.g., FFT, or other frequency, and/orspatial or other intrinsic parametric image data derived from the imagevia image processing and/or direct optical correlation of the existingk-space frequency field created in accordance with the present inventionfrom the imaged object or particle). Such techniques are described inmore detail below. Advanced image processing can characterize andcatalog images in real-time and/or periodic sample-measurements. Datacan be discarded and/or recorded as desired, whereas data matching knownsample characteristics can begin a suitable selected response, forexample. Furthermore, a device adapted in accordance with the presentinvention can be linked for communication in any data transmissionprocess. This can include wireless, broadband, wideband, ultra-wideband,phone modem, standard telecom, Ethernet or other network protocols(e.g., Internet, TCP/IP, Bluetooth, cable TV transmissions as well asothers).

[0221]FIG. 15 illustrates an excitation application 1400 in accordancewith an aspect of the present invention that can be employed with thesystems and processes previously described. A k-space system is adaptedin accordance with the present invention having a light system thatincludes a light source at 1410, such as a Light Emitting Diode (LED),emitting light having a wavelength of about 250 to about 400 nm (e.g.,ultraviolet light). The LED can be employed to provide forepi-illumination or trans-illumination as described herein (or othertype). The use of such an LED (or other UV light source) also enableswave-guide illumination in which the UV excitation wavelength isintroduced onto a planar surface supporting the object under test at1420, such that evanescent-wave coupling of the UV light can excitefluorophores within the object. For example, the UV light can be (butnot limited to) provided at about a right angle to a substrate on whichthe object lies. At 1430, the LED (or other light source or combinationsthereof) can emit light for a predetermined time period and/or becontrolled in a strobe-like manner emitting pulses at a desired rate.

[0222] At 1440, excitation is applied to the object for the perioddetermined at 1430. At 1450, automated and/or manual analysis isperformed on the object during (and/or thereabout) the excitationperiod. It is noted that the excitation application 1400 describedherein can apply to various processes. In one aspect, this includes aprocess wherein a high-energy photon (short wavelength) is absorbed andsubsequently re-emitted as a lower-energy photon (longer wavelength).The time interval between absorption and emission generally determineswhether the process is one of fluorescence or phosphorescence—which canalso be defined as a “down-conversion” process.

[0223] By way of illustration, the object which is sensitive toultraviolet in that it absorbs/emits photons in response to excitationof UV light from the light source. Fluorescence (or phosphorescence) isa condition of a material (organic or inorganic) in which the materialundergoes a process wherein a high-energy photon (short wavelength) isabsorbed and subsequently re-emitted as a lower-energy photon (longerwavelength). The time interval between absorption and emission generallydetermines whether the process is one of fluorescence orphosphorescence—which can also be defined as a “down-conversion”process. It can also continue to emit light while absorbing excitationlight. Both Fluorescence and phosphorescence can be an inherent propertyof a material (e.g., auto-fluorescence) or it can be induced, such as byemploying fluorochrome stains or dyes. The dye can have an affinity to aparticular protein, chemical component, physical component, and/or otherreceptiveness so as to facilitate revealing or discovering differentconditions associated with the object. In one particular example,fluorescence microscopy (or phosphorescence microscopy) and/or digitalimaging provide a manner in which to study various materials thatexhibit secondary fluorescence (or phosphorescence).

[0224] By way of further example, the UV LED (or other source) canproduce intense flashes of UV radiation for a short time period, with animage being constructed by a sensor (sensor adapted to the excitationwavelength) a short time later (e.g., milliseconds to seconds). Thismode can be employed to investigate the time decay characteristics ofthe fluorescent (or phosphorescent) components of the object (or sample)being tested. This may be important where two parts of the object (ordifferent samples) may respond (e.g., fluoresce/phosphorescencesubstantially the same under continuous illumination, but may havediffering emission decay characteristics.

[0225] As a result of using the UV light source, such as the LED, thelight from the light source can cause at least a portion of the objectunder test to emit light, generally not in the ultraviolet wavelength.Because at least a portion of the object fluoresces, (or phosphoresces)pre- or post-fluorescence/phosphorescence images can be correlatedrelative to those obtained during fluorescence/phosphorescence of theobject to ascertain different characteristics of the object. Incontrast, most conventional systems are configured to irradiate aspecimen and then to separate the weaker re-radiating fluorescent lightfrom the brighter excitation light, typically through filters. In orderto enable detectable fluorescence, such conventional systems usuallyrequire powerful light sources. For example, the light sources can bemercury or xenon arc (burner) lamps, which produce high-intensityillumination powerful enough to image fluorescence specimens. Inaddition to running hot (e.g., typically 100-250 Watt lamps), thesetypes of light sources typically have short operating lives (e.g.,10-100 hours). In addition, a power supply for such conventional lightsources often includes a timer to help track the number of use hours, asarc lamps tend to become inefficient and degrade with decreasing orvarying illumination output with use. The lamps are also more likely toshatter, if utilized beyond their rated lifetime. Moreover, conventionallight sources such as Xenon and mercury arc lamps (burners) generally donot provide even intensity across the desired emission spectrum fromultraviolet to infrared, as much of the intensity of the mercury burner,for example, is expended in wavelengths across the near ultraviolet.This often requires precision filtering to remove undesired lightwavelengths. Accordingly, it will be appreciated that using a UV LED, inaccordance with an aspect of the present invention, provides asubstantially even intensity at a desired UV wavelength to mitigatepower consumption and heat generated through its use. Additionally, thereplacement cost of a LED light source is significantly less thanconventional lamps.

[0226] In accordance with the foregoing discussion it will beappreciated that the excitation source may also be any other lightsource so desired for irradiation of an object through the k-spaceregion as described above. This could be, by way of example, anappropriate laser source. Such a laser source could be chosen to beapplicable to applications of Multi-photon Fluorescence Microscopy.

[0227] By way of further example, it will be appreciated that referringagain to FIG. 15 an excitation application is illustrated at 1400 inaccordance with an aspect of the present invention that can be employedwith the systems and processes previously described. A k-space system isadapted in accordance with the present invention having a light systemthat includes a Laser light source, such as (but not limited to)Ti:Sapphire Mode-Locked Lasers, and/or Nd:YLF Mode-Locked Pulsed Lasers.Such Lasers can be employed to provide for epi-illumination ortrans-illumination as described herein (or other type). The use of sucha Laser (or any other) also enables wave-guide illumination in which theexcitation wavelength is introduced onto a planar surface supporting theobject under test, such that evanescent-wave coupling of the Laser lightcan excite fluorophores within the object in accordance with the desiredparameters of Multi-photon Fluorescence Microscopy. For example, theLaser light can be (but not limited to) provided at about a right angleto a substrate on which the object lies. The Laser source (orcombinations thereof) can emit light for a predetermined time periodand/or be controlled in a strobe-like manner emitting pulses at adesired rate. Automated and/or manual analysis can be performed on theobject during (and/or thereabout) the excitation period. It is notedthat the excitation application described herein can apply to variousprocesses. In one aspect, this includes a process wherein Multi-photonFluorescence Microscopy is the desired result. The present invention maybe employed in any configuration desired (e.g., upright or inverted, orany other disposition such that the fundamental advantage of the opticaldesign is employable.)

[0228] Since excitation in multi-photon microscopy occurs at the focalpoint of a diffraction-limited microscope it provides the ability to“optically section” thick biological specimens in order to obtainthree-dimensional resolution. These “optical sections” are acquired,typically, by raster scanning the specimen in the x-y plane, and“building” a full “three-dimensional image” which is composed byscanning the specimen at sequential z positions in series. Multi-photonfluorescence is useful, for example, for probing selected regionsbeneath the specimen surface. This is because the position of the focalpoint can be accurately determined and controlled.

[0229] The lasers commonly employed in optical microscopy arehigh-intensity monochromatic light sources, which are useful as toolsfor a variety of techniques including optical trapping, lifetime imagingstudies, photo bleaching recovery, and total internal reflectionfluorescence. In addition, lasers are also the most common light sourcefor scanning confocal fluorescence microscopy, and have been utilized,although less frequently, in conventional wide field fluorescenceinvestigations.

[0230] It will be appreciated that an aspect of the present inventioncould incorporate a suitable exciting laser source. It is noted thattypical lasers employed for Multi-photon fluorescence currently includethe Ti:sapphire pulsed laser and Nd:YLF (neodymium: yttrium lithiumfluoride) laser (as well as other available laser sources.) The first isself mode-locked in operation and produces laser light over a broadrange of near-infrared wavelengths with variable pulse widths andgenerally adjustable speed. The exciting laser is joined to the presentinvention through a suitable port. This could be accomplished employingfiber coupling with an optical wave-guide or direct coupling with relaymirrors placed by design to direct the laser energy through the k-spaceregion to the object.

[0231] A typical multi-photon fluorescence microscope incorporates adetector system (e.g., a filtered photo multiplier or photodiode orother such detector to the laser wavelength) disposed in concert with anx-y raster scanning device which can rapidly deflect the focused laserbeam across the objective field. Digital images collected by themicroscope are processed and analyzed by a computer and associatedsoftware processing to assemble three-dimensional reconstructions fromthe “optical sections.” These images display typical of the imagesensor-visual microscope combination. Modern Multi-photon fluorescencemicroscopy has become a preferred technique for imaging living cells andtissues with three-dimensionally resolved fluorescence imaging sincetwo-photon excitation, which occurs at the focal point of themicroscope, minimizes photo bleaching and photo damage (the ultimatelimiting factors in imaging live cells.) This in itself allowsinvestigations on thick living tissue specimens that would not otherwisebe possible with conventional imaging techniques.

[0232] The mechanisms that enable sophisticated multi-photonfluorescence microscopy result from two-photon and three-photonexcitation, for example. These occur when two or three photons areabsorbed by fluorophores in a quantitized event. Photons can, in thisway be absorbed at high enough photon by combining their energies toforce an electronic transition of a fluorosphore to the excited state.

[0233]FIG. 16 illustrates a thin films application 1500 in accordancewith an aspect of the present invention. Films and thin films can becharacterized in general terms as thin layers (varying from molecularthickness(es) to significant microscopic to macroscopic thickness(es) ofsome material, or multiple materials, deposited in a manner suitable torespective materials onto various substrates of choice and can include(but are not limited to) any of the following: metallic coating (e.g.,reflective, including partial, opaque, and transmissive), opticalcoatings (e.g., interference, transmission, anti-reflective, pass-band,blocking, protective, multi-coat, and so forth), plating (e.g.,metallic, oxide, chemical, anti-oxidant, thermal, and so forth),electrically conductive (e.g., macro and micro-circuit deposited andconstructed), optically conductive (e.g., deposited optical materials ofvarying index of refraction, micro- and macro-optical “circuits.”). Thiscan also include other coatings and layered film and film-like materialson any substrate which can be characterized by deposition in variousmanners so as to leave a desired layer or multiplicity of layers of somematerial(s) on said substrate in a desired thickness, consistency,continuity, uniformity, adhesion, and other parameters associated withany given deposited film. Associated thin film analysis can include, butis not limited to detection of micro bubbles, voids, microscopic debris,depositing flaws, and so forth.

[0234] Proceeding to 1510, a k-space system is configured for thin filmanalysis in accordance with an aspect of the present invention. Theapplication of a k-space imaging device to the problem of thin-filminspection and characterization can be employed in identifying andcharacterizing flaws in a thin film layer or multiplicity of layers ofthin films for example. Such a system can be adapted to facilitate:

[0235] 1) manual observation of a substrate with deposited thin film ofall types;

[0236] 2) automatic observation/analysis and characterization of asubstrate with deposited thin film of all types for pass-failinspection;

[0237] 3) automatic observation and characterization of a substrate withdeposited thin film of all types for computer-controlled comparativedisposition, this can include image data written to recording media ofchoice (e.g., CD-ROM, DVD-ROM) for verification, certification, and soforth.

[0238] A k-space device can be configured for imaging at desiredAbsolute Spatial Resolution (ASR) per pixel and desired EffectiveResolved Magnification (ERM). These parameters facilitate determiningFOV, DOF, and WD, for example. This can include objective-based designconfigurations and/or achromat-design configurations (e.g., for wide FOVand moderate ERM, and ASR). Illumination can be selected based oninspection parameters as trans-illumination and/or epi-illumination, forexample.

[0239] At 1520, a substrate is mounted in an imager in such a manner asto enable a defined area of, or an entire area of interest of thesubstrate to be scanned by:

[0240] 1) movement of an optical imaging path-length by optical scanningmethod; and/or

[0241] 2) indexing an object being tested directly by a process ofmechanical motion and control (e.g., automatic by computer or manual byoperator). This facilitates an inspection of an entire surface orportion of the surface as desired.

[0242] As noted above in context of particle sizing, asynchronous orsynchronous imaging at selected timing intervals and/or in real-time forrespective scanned areas (e.g., determined by FOV) of substrate atcommon video rates and/or at image capture rates can be provided. Imagesof indexed and/or scanned areas can be captured with desired frequencyfor subsequent image processing. In addition, samples can be introducedinto the device manually and/or in an automated manner from a “feed”such as from a conveyor system.

[0243] At 1530, operational parameters for thin film applications aredetermined and applied. Typical operational parameters can include butare not limited to:

[0244] 1) Imaging of various flaws and characteristics including, butnot limited to, particles and holes on a surface(s) (or within) a thinfilm or multiplicity of layers of such films;

[0245] 2) Modular designs which can be varied as needed for bothreflective and transparent films and/or substrates and/or surfaces;

[0246] 3) Automated counting and categorization of surface flaws bysize, location, and/or number on successively indexed (and/or “scanned”)image areas (with index identification and totals for respective samplesurfaces);

[0247] 4) Register location of defects for subsequent manual inspection;

[0248] 5) Provide images in standard format(s) for subsequent porting(e.g., via Ethernet or other protocol) or manual and/or automated imageprocessing for archive and documentation on a computer, server, and/orclient and/or remote transmission via any selected data transmissionprotocol;

[0249] 6) Nominal scan time per surface of seconds to minutes dependenton total area.

[0250] Scan and indexing speed generally understood to vary with samplearea and subsequent processing.

[0251] At 1540, software and/or hardware based computerized imageprocessing/analysis can occur. Images from a device adapted inaccordance with the present invention can be processed in accordancewith substantially any hardware and/or software process. Software-basedimage processing can be achieved by custom software and/or commerciallyavailable software since the image file formats are digital formats(e.g., bit maps, TIFF, JPEG, and so forth or any other digital imagefile format (or combinations thereof) of captured images of films).

[0252] Analysis, characterization and so forth can also be provided bythe following: For example, analyses can be metrologic (directmeasurement based) correlative, and/or comparative (data-base) based.Correlative and/or comparative analyses can include comparisons to adatabase of (but not limited to) complete/partial visual image data,and/or component image data (e.g., FFT, or other frequency, and/orspatial or other intrinsic parametric image data derived from the imagevia image processing and/or direct optical correlation of the existingk-space frequency field created in accordance with the present inventionfrom the imaged thin film). Such techniques are described in more detailbelow.

[0253] Advanced image processing can characterize and catalog images inreal-time and/or periodic sample-measurements. Data can be discardedand/or recorded as desired, whereas data matching known samplecharacteristics can begin a suitable selected response, for example.Furthermore, a device adapted in accordance with the present inventioncan be linked for communication in any data transmission process. Thiscan included wireless, broadband, wideband, ultra-wideband, phone modem,standard telecom, Ethernet or other network protocols (e.g., Internet,TCP/IP, Bluetooth, cable TV transmissions as well as others). It is tobe appreciated that imaging of substrate material in accordance with thepresent invention can be provided on a substantially absolute scale ofquality control and traceable via image storage, whereas currenttechniques typically only provide statistical quality control and areoften intensely labor-based with no associated stored images.

[0254] In another aspect of the present invention, an imaging systemadapted as described above provides high Effective ResolvedMagnification and high Absolute Spatial Resolution among other featuresof biological material and methods that can be combined to provideimproved biological material imaging systems and methods. The biologicalmaterial imaging systems and methods of the present invention enable theproduction of improved images (higher Effective Resolved Magnification(ERM), improved Absolute Spatial Resolution (ASR), improved depth offield, and the like) leading to the identification of biologicalmaterials as well as the classification of biological materials (forexample as normal or abnormal).

[0255] Biological material includes microorganisms (organisms too smallto be observed with the unaided eye) such as bacteria, virus,protozoans, fungi, and ciliates; cell material from organisms such cells(lysed, intracellular material, or whole cells), proteins, antibodies,lipids, and carbohydrates, tagged or untagged; and portions of organismssuch as clumps of cells (tissue samples), blood, pupils, irises, fingertips, teeth, portions of the skin, hair, mucous membranes, bladder,breast, male/female reproductive system components, muscle, vascularcomponents, central nervous system components, liver, bone, colon,pancreas, and the like. Since the biological material imaging system ofthe present invention can employ a relatively large working distancewith the advantage of higher ERM and ASR than conventionalinstrumentation has traditionally allowed, portions of the human bodymay be directly examined without the need for removing a tissue sample.

[0256] Cells include human cells, non-human animal cells, plant cells,and synthetic/research cells. Cells include prokaryotic and eukaryoticcells. Cells may be in microscopic tissue samples, microtomed (or thelike) slices of tissue, or individual cells or multi-cellular groupswhich have been micro-dissected or resected by any appropriate means.Cells may be healthy, cancerous, mutated, damaged, or diseased.

[0257] Examples of non-human cells include anthrax, Actinomycetes spp.,Azotobacter, Bacillus anthracis, Bacillus cereus, Bacteroides species,Bordetella pertussis, Borrelia burgdorferi, Campylobacterjejuni,Chlamydia species, Clostridium species, Cyanobacteria, Deinococcusradiodurans, Escherichia coli, Enterococcus, Haemophilus influenzae,Helicobacter pylori, Klebsiella pneumoniae, Lactobacillus spp., Lawsoniaintracellularis, Legionellae, Listeria spp., Micrococcus spp.,Mycobacterium leprae, Mycobacterium tuberculosis, Myxobacteria,Neisseria gonorrheoeae, Neisseria meningitidis, Prevotella spp.,Pseudomonas spp., Salmonellae, Serratia marcescens, Shigella species,Staphylococcus aureus, Streptococci, Thiomargarita namibiensis,Treponema pallidum, Vibrio cholerae, Yersinia enterocolitica, Yersiniapestis, and the like.

[0258] Additional examples of biological material are those that causeillness such as colds, infections, malaria, chlamydia, syphilis,gonorrhea, conjunctivitis, anthrax, meningitis, botulism, diarrhea,brucellosis, campylobacter, candidiasis, cholera, coccidioidomycosis,cryptococcosis, diphtheria, pneumonia, foodborne infections, glanders(burkholderia mallei), influenzae, leprosy, histoplasmosis,legionellosis, leptospirosis, listeriosis, melioidosis, nocardiosis,nontuberculosis mycobacterium, peptic ulcer disease, pertussis,pneumonia, psittacosis, salmonella enteritidis, shigellosis,sporotrichosis, strep throat, toxic shock syndrome, trachoma, typhoidfever, urinary tract infections, lyme disease, and the like. Asdescribed later, the present invention further relates to methods ofdiagnosing any of the above illnesses.

[0259] Examples of human cells include fibroblast cells, skeletal musclecells, neutrophil white blood cells, lymphocyte white blood cells,erythroblast red blood cells, osteoblast bone cells, chondrocytecartilage cells, basophil white blood cells, eosinophil white bloodcells, adipocyte fat cells, invertebrate neurons (Helix aspera),mammalian neurons, adrenomedullary cells, melanocytes, epithelial cells,endothelial cells; tumor cells of all types (particularly melanoma,myeloid leukemia, carcinomas of the lung, breast, ovaries, colon,kidney, prostate, pancreas and testes), cardiomyocytes, endothelialcells, epithelial cells, lymphocytes (T-cell and B cell), mast cells,eosinophils, vascular intimal cells, hepatocytes, leukocytes includingmononuclear leukocytes, stem cells such as haemopoetic, neural, skin,lung, kidney, liver and myocyte stem cells, osteoclasts, chondrocytesand other connective tissue cells, keratinocytes, melanocytes, livercells, kidney cells, and adipocytes. Examples of research cells includetransformed cells, Jurkat T cells, NIH3T3 cells, CHO, COS, etc.

[0260] A useful source of cell lines and other biological material maybe found in ATCC Cell Lines and Hybridomas, Bacteria and Bacteriophages,Yeast, Mycology and Botany, and Protists: Algae and Protozoa, and othersavailable from American Type Culture Co. (Rockville, Md.), all of whichare herein incorporated by reference. These are non-limiting examples asa litany of cells and other biological material can be listed.

[0261] The identification or classification of biological material canin some instances lead to the diagnosis of disease. Thus, the presentinvention also provides improved systems and methods of diagnosis. Forexample, the present invention also provides methods for detection andcharacterization of medical pathologies such as cancer, pathologies ofmusculoskeletal systems, digestive systems, reproductive systems, andthe alimentary canal, in addition to atherosclerosis, angiogenesis,arteriosclerosis, inflamation, atherosclerotic heart disease, myocardialinfarction, trauma to arterial or veinal walls, neurodegenerativedisorders, and cardiopulmonary disorders. The present invention alsoprovides methods for detection and characterization of viral andbacterial infections. The present invention also enables assessing theeffects of various agents or physiological activities on biologicalmaterials, in both in vitro and in vivo systems. For example, thepresent invention enables assessment of the effect of a physiologicalagent, such as a drug, on a population of cells or tissue grown inculture.

[0262] The biological material imaging system of the present inventionenables computer driven control or automated process control to obtaindata from biological material samples. In this connection, a computer orprocessor, coupled with the biological material imaging system, containsor is coupled to a memory or data base containing images of biologicalmaterial, such as diseased cells of various types. In this context,automatic designation of normal and abnormal biological material may bemade. The biological material imaging system secures images from a givenbiological material sample, and the images are compared with images inthe memory, such as images of diseased cells in the memory. In onesense, the computer/processor performs a comparison analysis ofcollected image data and stored image data, and based on the results ofthe analysis, formulates a determination of the identity of a givenbiological material; of the classification of a given biologicalmaterial (normal/abnormal, cancerous/non-cancerous, benign/malignant,infected/not infected, and the like); and/or of a condition (diagnosis).

[0263] If the computer/processor determines that a sufficient degree ofsimilarity is present between particular images from a biologicalmaterial sample and saved images (such as of diseased cells or of thesame biological material), then the image is saved and data associatedwith the image may be generated. If the computer/processor determinesthat a sufficient degree of similarity is not present between particularimage of a biological material sample and saved images of diseasedcells/particular biological material, then the biological materialsample is repositioned and additional images are compared with images inthe memory. It is to be appreciated that statistical methods can beapplied by the computer/processor to assist in the determination that asufficient degree of similarity is present between particular imagesfrom a biological material sample and saved images of biologicalmaterial. Any suitable correlation means, memory, operating system,analytical component, and software/hardware may be employed by thecomputer/processor.

[0264] Referring to FIG. 17, an exemplary aspect of an automatedbiological material imaging system 1600 in accordance with one aspect ofthe present invention enabling computer driven control or automatedprocess control to obtain data from biological material samples isshown. An imaging system 1602 described/configured in connection withFIGS. 1-16 above may be employed to capture an image of a biologicalmaterial 1604. The imaging system 1602 is coupled to a processor 1606and/or computer that reads the image generated by the imaging system1602 and compares the image to a variety of images in the data store1608.

[0265] The processor 1606 contains an analysis component to make thecomparison. Some of the many algorithms used in image processing includeconvolution (on which many others are based), FFT, DCT, thinning (orskeletonisation), edge detection, pattern recognition, and contrastenhancement. These are usually implemented in software but may also usespecial purpose hardware for speed. FFT (fast Fourier transform) is analgorithm for computing the Fourier transform of a set of discrete datavalues. Given a finite set of data points, for example, a periodicsampling taken from a real-world signal, the FFT expresses the data interms of its component frequencies. It also addresses the essentiallyidentical inverse concerns of reconstructing a signal from the frequencydata. DCT (discrete cosine transform) is technique for expressing awaveform as a weighted sum of cosines. There are several applicationsdesigned for image processing, e.g., CELIP (cellular language for imageprocessing) and VPL (visual programming language).

[0266] The data store 1608 contains one or more sets of predeterminedimages. The images may include normal images of various biologicalmaterials and/or abnormal images of various biological materials(diseased, mutated, physically disrupted, and the like). The imagesstored in the data store 1608 provide a basis to determine whether ornot a given captured image is similar or not similar (or the degree ofsimilarity) to the stored images. In one aspect, the automatedbiological material imaging system 1600 can be employed to determine ifa biological material sample is normal or abnormal. For example, theautomated biological material imaging system 1600 can identify thepresence of diseased cells, such as cancerous cells, in a biologicalmaterial sample, thereby facilitating diagnosis of a given disease orcondition. In another aspect, the automated biological material imagingsystem 1600 can diagnose the illnesses/diseases listed above byidentifying the presence of an illness causing biological material (suchas an illness causing bacteria described above) and/or determining thata given biological material is infected with an illness causing entitysuch as a bacteria or determining that a given biological material isabnormal (cancerous).

[0267] In yet another aspect, the automated biological material imagingsystem 1600 can be employed to determine the identity of a biologicalmaterial of unknown origin. For example, the automated biologicalmaterial imaging system 1600 can identify a white powder as containinganthrax. The automated biological material imaging system 1600 can alsofacilitate processing biological material, such as performing whiteblood cell or red blood cell counts on samples of blood, for example.

[0268] The computer/processor 1606 may be coupled to a controller whichcontrols a servo motor or other means of moving the biological materialsample within an object plane so that remote/hands free imaging isfacilitated. That is, motors, adjusters, and/or other mechanical meanscan be employed to move the biological material sample slide within theobject field of view.

[0269] Moreover, since the images of the biological material examinationprocess are optimized for viewing from a computer screen, television,and/or closed circuit monitor or other such as described previously,remote and web based viewing and control may be implemented. Real timeimaging facilitates at least one of rapid diagnosis, datacollection/generation, and the like.

[0270] In another aspect, the biological material imaging system isdirected to a portion of a human (such as lesion on an arm, haze on thecornea, and the like) and images formed. The images can be sent to acomputer/processor (or across network such as Internet), which isinstructed to identify the possible presence of a particular type ofdiseased cell (an image of which is stored in memory). When a diseasedcell is identified, the computer/processor instructs the system toremove/destroy the diseased cell, for example, employing a laser, liquidnitrogen, cutting instrument, and/or the like.

[0271]FIG. 18 depicts a high-level machine vision/analysis system 1800in accordance with the subject invention. The system 1800 includes animaging system 10 (FIG. 1) in accordance with the subject invention. Theimaging system 10 is discussed in substantial detail supra and thusfurther discussion regarding details related thereto is omitted for sakeof brevity. The imaging system 10 can be employed to collect datarelating to a product or process 1810, and provide the image informationto a controller 1820 that can regulate the product or process 1810, forexample, with respect to production, process control, quality control,testing, inspection, etc. The imaging system 10 as noted above providesfor collecting image data at a granularity not achievable by manyconventional systems. Moreover, the robust image data provided by thesubject imaging system 10 can afford for highly effective machine visioninspection of the product or process 1810. For example, minute productdefects typically not detectable by many conventional machine visionsystems can be detected by the subject system 1800 as a result of theimage data collected by the imaging system 10. The controller 1810 canbe any suitable controller or control system employed in connection witha fabrication scheme, for example. The controller 1810 can employ thecollected image data to reject a defective product or process, revise aproduct or process, accept a product or process, etc. as is common tomachine-vision based control systems. It is to be appreciated that thesystem 1800 can be employed in any suitable machine-vision basedenvironment, and all such applications of the subject invention areintended to fall within the scope of the hereto appended claims.

[0272] For example, the subject system 1800 could be employed inconnection with semiconductor fabrication where device and/or processtolerances are critical to manufacturing consistent reliablesemiconductor-based products. Thus, the product 1810 could represent asemiconductor wafer, for example, and the imaging system 1800 could beemployed to collect data (e.g., critical dimensions, thicknesses,potential defects, other physical aspects . . . ) relating to devicesbeing formed on the wafer. The controller 1820 can employ the collecteddata to reject the wafer because of various defects, modify a process inconnection with fabricating devices on the wafer, accept the wafer, etc.

[0273] There are many instances where the imaging systems and processesof the present invention can facilitate semiconductor processing and/orfabrication. The imaging system of the present invention can one or moreof inspect, monitor, and facilitate, in real time or post-processing,the formation of trenches, the formation of vias, the formation of dualdamascene openings, the development of a photoresist, the formation ofmetal lines, the formation of spacers, the formation of metalinterconnects, the deposition and/or etching of a dielectric material,the formation of gates including MOSFETs and non-volatile memory cells,the formation of bitlines and/or wordlines, chemical mechanicprocessing, the formation of an implant region, the patterning of ametal layer, the patterning of a dielectric layer, the patterning of apolysilicon layer, and the like.

[0274] The imaging system of the present invention can inspect fordefects in a given structure once formed (defects as contaminants or asphysical deformities). Consequently, the imaging system of the presentinvention can facilitate and/or improve fabrication of centralprocessing units (CPUs), read only memory chips (ROMs), random accessmemory chips (RAMs), dynamic random access memory devices (DRAMs),static random access memory devices (SRAMs), input-output chips (IOs),non-volatile memory devices such as programmable read only memorydevices (PROMs), erasable programmable read only memory devices(EPROMs), and electrical erasable programmable read only memory devices(EEPROMs), video game chips, and the like.

[0275] The imaging system of the invention can be employed in exposureequipment to contact light with a semiconductor structure, such asduring photolithography. The imaging system of the invention can beemployed to align the semiconductor structure, inspect the semiconductorstructure, inspect/align a reticle, and the like.

[0276] The imaging system of the present invention can facilitateoptical networking component processing and/or fabrication. Opticalnetworking components include optical integrated circuits, planarlightwave circuits, optical fiber connection devices, and the like. Theimaging system of the present invention can facilitate liquid crystaldevice processing and/or fabrication and plasma display deviceprocessing and/or fabrication.

[0277] The imaging system of the present invention can facilitaterecording media processing and/or fabrication. Recording media includedata recording media, optical disks, compact disks (CDs), laser disks(LDs), digital video disks (DVDs), hard disk drives (HDDs), magneticdisks, memory sticks, video cards, and the like. For example, a CDcontains a long string of pits and/or grooves written helically on thedisk. An exemplary process begins by making a glass master (many otherprocesses exist) by lapping flat and polishing a glass plate. The plateis coated with photoresist. A mastering tape is made containing theinformation to be written on the disk. A laser then writes the patternfrom the master tape into the photoresist. The photoresist is developed.The imaging system of the present invention can inspect/monitor in realtime and/or after development. A layer of metal is evaporated over thephotoresist. Again, the imaging system of the present invention caninspect/monitor in real time or after metal deposition. The master isthen checked for accuracy by playing the disk. The master is thensubject to an electroforming process. In this electrochemical process,additional metal is deposited. When the metal is thick enough, the metallayer is separated from the glass master. This results in a metalnegative impression of the disk called a father. The electroplatingprocess is then repeated on the father. This typically generates severalpositive metal impressions from the father before the quality of thefather degrades unacceptably. These impressions are called mothers. Theelectroplating process is repeated again on the mothers. Fabrication ofthe father and mothers can be checked or monitored by the imaging systemof the present invention. Each mother typically makes several negativemetal impressions called sons or stampers. The sons are suitable asmolds for injection molding. Polycarbonate is often used to injectionmold the CDs. Once the disks are molded, a metal layer is used to coatthe disks. Following metal deposition, a thin plastic layer is spincoated on over the metal. The imaging system of the present inventioncan inspect/monitor in real time, before, during, and/or after one ormore of the molding process, the metal coating process, and plasticspin-coating process.

[0278]FIG. 19 illustrates an exemplary automated inspection and/ormanufacturing system 1900 and process in accordance with an aspect ofthe present invention. The system 1900 includes 1 through J analyzers, Jbeing an integer, depicted at reference numerals 1920 through 1928having associated k-space optics 1930 though 1938 which are adapted inaccordance with the sensor and optical parameters described above (e.g.,correlating optical diffraction limited point with sensor pitch). Anautomated transport 1950 receives/moves/manipulates one or more objects1960 as part of an automatic, semi-automatic and/or manual manufacturingand/or inspection operation (e.g., conveyors, belts, drives, directionalconveyor sections, automated assembly/inspection lines/cells, and soforth). It is noted that transport of object 1960 (or positioningthereof) is not limited to straight-line transport (e.g., translationalmovements of objects and/or analyzers/optics in multiple dimensions suchas from robotic movements and so forth).

[0279] The objects 1960 flow within range of the optics 1930-1938(analyzers and associated optics can also move toward object at variousangles), whereby the speed of the automated transport 1950 (or movementof analyzer/optics) may decrease or stop to enable an inspection and/ormanufacturing operation. For example, the object 1960 may flowunderneath the optics at 1930, wherein an image of the object (orportions therein) is captured by the analyzer 1920 via the optics. Asthe object 1960 flows down the transport 1950, subsequent image capture,analysis, and/or assembly can occur at analyzers 1924 and 1928,respectively. It is to be appreciated that object flow or movement forimage capture can be from above or from the side or at other angles aswell,—depending on positioning of object with respect to the optics1930-1938. Automated imaging can include moving analyzers and/or opticswith respect to objects, moving objects with respect toanalyzers/optics, and/or combinations of movements betweenanalyzers/optics, objects and transport mechanisms. Furthermore,respective analyzer stations 1920-1928 may be equipped with a pluralityof respective optics and associated sensors for inspecting/manufacturingmultiple objects and/or multiple portions associated with a respectiveobject or objects.

[0280] The analyzers 1920-1928 include one or more sensors, memories,and computer components and can include processor and/ormulti-processor/controller/I/O components to acquire/store/analyze arespective image, wherein the image is generally composed of digitalbits of all or portions of the object 1960 as received/viewed from theoptics 1930-1938. Respective images may also include data in proximityto the object 1960 such as between objects and/or at object peripheries.When the image has been captured in analyzer memory, a plurality ofvarious measurements, calculations, computations, and/or algorithms canbe performed on the image to determine if the object 1960 and/orportions associated with the object 1960 fall within or exceed desiredor predetermined performance criteria (e.g., optical measurementwithin/outside predetermined parameter threshold, object 1960 orportions thereof compared to calibrated images in a database or memory).These determinations are described in more detail with respect to FIG.20.

[0281] It is noted that analyzers 1920-1928 can include industrialcontrol aspects and operate as isolated and/or coordinated manufacturingcells having communications there between (e.g., wireless and/ornetworked communications between cells and can include transportingimage data to remote locations across networks such as the Internet forstorage/analysis and/or control purposes). The industrial controlaspects can be utilized to control the automated transport 1950, theanalyzers and/or associated optics, and/or to control other portions ofthe system 1900. For example, feedback from the analyzers utilizingrespective image data can be employed to control other machinery (notshown) (e.g., PLC's and associated I/O) in a closed loop or open loopmanner when operating upon, or manufacturing, all or portions of theobject 1960 as the object travels on the automated transport 1950 (e.g.,controlling/inspecting semiconductor processes, welders, robots,machines, drills, cutters, water jets, valves, solenoids, films, otherprocesses described previously and so forth). This can include roboticand/or other automated movements of the analyzers 1920-1928 and/orassociated optics 1930-1938 when performing manufacturing/inspectionoperations. As can be appreciated, similar movements and/or measurementspreviously described can be employed in a machine vision and/orautomated inspection context. Such inspection can include qualitycontrol and/or other metrics, wherein the object 1960 (or portionsthereof) is categorized, approved, rejected, flagged, removed,discarded, passed to another cell and so forth.

[0282] It is to be appreciated that the automatedmanufacturing/inspection system 1900 depicted in FIG. 19 is intended toillustrate exemplary aspects of an automated system or process. As such,a plurality of other manufacturing cells, transports, robots,communications, computers, controllers, other equipment, and so forthwhich are not shown may also be included in an automated environment.For example, after an object has been processed on the automatedtransport 1950, a robotic, automated, and/or manual operation may placethe respective object on another line or cell (not shown) for furtherinspection, manufacturing and/or process such as for further processingor packaging the object 1960 for shipping, as an example. As can beappreciated, the analyzers 1920-1928 and associated optics 1930-1938 canbe adapted to inspect/manufacture similar parameters/portions of arespective object or objects such as a parallel inspection/assemblyoperation, wherein a plurality of objects are inspected/manufactured ina concurrent manner and in accordance with a similar process.

[0283] In another aspect, the analyzers and associated optics can beadapted according to different aspects, wherein a respective cell isconfigured to inspect/manufacture one portion of a respective object andanother cell is configured to inspect/manufacture a different orsubsequent portion of a respective object in a serial manner. Inaddition, the present invention can operate in accordance with acombination of serial and/or parallel inspection/assembly operations,wherein a plurality of cells are adapted to cooperate in some instancesin a concurrent manner, in some instances in a serial manner, and inother instances in a combination of serial, parallel and/or concurrentoperations. As can further be appreciated, adaptations of one or morecells can be achieved via software/programmatic configurations, hardwareconfigurations, and/or combinations thereof.

[0284]FIG. 20 illustrates exemplary objects for inspection and/ormanufacturing in accordance with an aspect of the present invention. Asone example of an object, a semiconductor wafer is illustrated at 2000.The wafer 2000 is depicted as having at least one segment whereinrespective segments are associated with a darkened point forillustrative purposes. These points—which do not necessarily have to beassociated with a wafer 2000, can represent substantially any type ofsemiconductor portion, circuit, and/or feature (mechanical, material,and/or electrical). Such portions or features include for example, butare not limited to: any type of circuits, gates, memories, transistors,FET's, logic devices, diodes, films, LED's, organic devices, displays,LCD's, resistors, capacitors, inductors, fuses, amplifiers, oscillators,timers, counters, micro-code sections, gate arrays, programmable gatearrays, PLD's, PAL's, microprocessors, micro-controllers, computers,micro-machines, micro-portions or elements, MEM's devices, bondingelements, connecting wires, vias, openings, traces, lines, patterns—anytype (e.g., point, 2D, 3D), trenches, grooves, separations, spaces,distance between elements, layers, stacks of layers, portions orelements having different depths, electrical/mechanical shorts/opens,and so forth.

[0285] In a more generalized discussion of objects that may bemanufactured and/or inspected in accordance with the present invention,three exemplary items are illustrated at 2010 through 2030. At 2010, anangular structure is depicted, whereas a cylindrical and a cubicstructure are illustrated at 2020 and 2030 (other shapes/dimensions maybe employed). These exemplary objects 2010-2030 can beanalyzed/manufactured for substantially any type of dimensional aspect(objects do not have to be three dimensional). For example, the objectat 2010 can represent a trace and can be analyzed for width, length,depth, and proximity to other objects, if desired, including suchaspects as critical dimensions, line widths, line spacing, line quality,opens, shorts, pattern match or pattern quality and so forth. Objects2020 and 2030 can represent such features as for example: vias,openings, raised features, indented features, recessed features,grooves, trenches, connectors, and so forth.

[0286] As can be appreciated other type features and other type objectscan be analyzed, inspected, and/or manufactured in accordance with thepresent invention. Proceeding to diagram 2050 of FIG. 20, and atreference 2060, substantially any type of object can be processed havingsubstantially any type shape, color, transparency, opaqueness, size,composition and/or material. Such objects can include for example:points, lines, planes, circles, squares, rectangles, ellipsoids,triangular structures, polygonal structures, spherical structures, cubicstructures, cylindrical structures, trapezoidal structures, columns, andvarious combinations thereof. At 2070, substantially any dimensionalaspect of an object can be measured in accordance with the presentinvention. Such dimensions include for example, length, width, depth,angles, separations between objects, pattern matching, color matching,and so forth. As noted above, predetermined thresholds can beestablished. For example, if a line object is measured for a width orlength, predetermined thresholds can be set or configured, wherein ifthe line measures within a range (e.g., not too long/not too short, notto wide, not too narrow) then the line can be categorized as beingwithin specifications, otherwise, the measured line can be rejectedand/or logged as not meeting specifications. Alternatively, objects canbe compared with existing images of object portions within a databasefor example, wherein analysis can be based on a plurality of criteriasuch as the number of matching pixels between a measured object and astored object or object portion. As can be appreciated, such analysiscan include substantially any custom or commercially available softwareto facilitate such analysis.

[0287] At 2080, not only can respective objects or features be analyzedas previously discussed, but features and dimensions within portions ofrespective objects or associated with respective objects can besimilarly analyzed. Thus, any given object to be analyzed can includevarious combinations of materials, properties, parameters, and/orfeatures previously described within all or portions of the object.Likewise, a given object to analyze may include a combination of smallerobjects that are similarly or differently configured that cooperate toform the object under inspection or manufacture. At 2090, all orportions of the above processes, analysis, determinations, and/ormeasurements can be employed in an automated inspection and/ormanufacturing operation. Such aspects can include utilizing the abovedeterminations and measurements in a control loop, control feedback,and/or control algorithm to facilitate such operations.

[0288]FIG. 21 illustrates various exemplary analytical techniques 2100that may be employed for component, particle, and/or materialidentification and/or analysis in accordance with an aspect of thepresent invention. It is to be appreciated that the analyticaltechniques 2100 can be applied with any of the systems, processes,and/or particles/materials/objects/shapes . . . and so forth describedherein. An analyzer 2110 is provided to identify, analyze and/ordetermine one or more items such as an object, component, particleand/or material, for example. The analyzer 2110 can include automatedtechniques such as software operating on a computer, wherein respectiveitems to be analyzed are first imaged and analyzed in accordance with aplurality of previously stored components, images, and/or parameters ina database or file to facilitate identification/analysis of therespective item. It is to be appreciated that item identification canalso include manual analysis such as viewing an image from a display orinvoking software that inputs an image to be analyzed, for example,and/or include combinations of manual and/or automated techniques.Software can include commercially available software (e.g., Matlab)and/or include developer software to facilitate the analysis (e.g.,write Visual C++ routine employing equations, artificial intelligence orstatistical models).

[0289] The analyzer 2110 includes one or more of the following exemplarytechniques/components to identify/analyze an item in accordance with thepresent invention, although it is to be appreciated that othertechniques may be employed. At 2120, comparative techniques can beemployed. This includes comparing captured images to previously storedimages on a database to determine a match (or close to a match definedby predetermined matching criteria), performing database lookups, and/orperforming digital subtraction between images to determine differences(e.g., after performing subtraction, making a particle identificationbased on fewest non-subtracted bits appearing in a resultant bit map).At 2130, correlative analysis can be applied. Correlative analyses caninclude comparisons to a database of (but not limited too) eithercomplete/partial visual image data, and/or component image data (e.g.,FFT, or other frequency, and/or spatial or other intrinsic parametricimage data derived from the image via image processing and/or directoptical correlation of the existing k-space frequency field created inaccordance with the present invention from the imaged object, component,particle, and or materials, for example). Such techniques are describedin more detail below with reference to FIGS. 22 and 23.

[0290] At 2140, intelligent and/or learning systems can be applied foritem identification. Such aspects include neural networks, classifiers,inference models, artificial intelligence and/or other learning models(e.g., Support Vector Machines (SVM), Bayes, Naive Bayes, Bayes Net,decision tree, similarity-based, vector-based, Hidden Markov Modelsand/or other learning models or combinations thereof) (can includehand-crafted models). The learning systems 2140 are trained to identify(or infer) an item based upon past training (or inferences) of similaritems, wherein an imaged item is input to a trained model foridentification purposes. It is noted that combinations of learningmodels or systems can be employed including hierarchical arrangements ofsuch models, wherein output from one or more models is provided to asubsequent model or set of models for further analysis or inference.This also includes substantially any statistical and/or probabilistictechnique, process, equation and/or algorithm for analyzing an item andmaking an identification based upon statistical, analytical and/orprobabilistic similarities or differences with previously stored imagesor parameters (e.g., making an identification by determining if itemmeasurements or samples fall within statistical and/or probabilisticthresholds).

[0291] Proceeding to 2150, parametric analysis can be provided fordetermining an item. In this aspect, a captured image is automaticallyparameterized for such characteristics as size, shape, morphology,thickness, other objects or vacancies appearing therein, diameter,length, circumference, three-dimensional qualities, and so forth. Whenthe parameters have been determined, previously stored parameters forknown particles are then compared to the determined parameters. If anitem compares favorably (within predetermined threshold) of a storedparameter or parameter set associated with a known particle, then anidentification can be made based upon the parametric comparison orsimilarity.

[0292] At 2160, a cause and effect analysis can be provided inaccordance with the present invention. In this aspect, items areobserved for known reactions to specified events and/or applicationsthereof (measurements or images can also be captured over time or atpredetermined times after event). For example, this can include itemreactions to illumination, radiation, and temperature variations basedupon an application of such events. Thus, if temperature were increasedor decreased for a respective item as the event or cause, for example,and the imaged item contracted or expanded over time in accordance witha known contraction or expansion as the reaction or effect to therespective event, then an item identification can be made based upon acomparison to other known reactions (contraction/expansion of particlesize/shape) that have been previously stored or cataloged.

[0293] Other reactive causes or stimulating events can includeobservations or determinations of chemical reactions, mechanicalreactions (e.g., reaction to shock, vibration oscillation, motion and soforth), mixing reactions such as mixing an item with another item andobserving interactions and/or distributions of the respective items,and/or electrical reactions (e.g., applying voltages, currents, magneticfields, electrical fields, frequencies, waves, and so forth to arespective item, observing the effect of such electrical stimuli, andcomparing the effects with known samples that have been similarlystimulated and/or comparisons with data derived/modeled therefrom).

[0294]FIGS. 22 and 23 relate to correlative imaging techniques inaccordance with an aspect of the present invention. Correlative and/orcomparative analyses can include (but not limited too) comparisons to adatabase of visual image data, and/or component image data (e.g., FFT,or other frequency, and/or spatial or other intrinsic parametric imagedata derived from the image via image processing or direct opticalcorrelation of existing k-space frequency field created in accordancewith present invention from the imaged object.) The existing frequencyfield created in the infinity-space volume of the present invention canbe exploited and directed employing optical components. For example, theFourier Transform or uncorrelated FFT, which exists in the k-spacevolume, can be employed as previously mentioned for optical correlationwith an existing database of directly and/or empirically derivedcataloged Fourier Transform or FFT data or Image-Processingtransformation-based cataloged FFT data.

[0295] Referring now to FIG. 22, a configuration 2200 defines that anexisting, unmodified k-space Fourier Transform or FFT itself be imagedby an image array (CCD, CMOS, CID, and so forth) at 2210 and then thatimage (which is the extant actual FFT which can be appreciated as an“instant FFT or “unprocessed FFT”) can be compared via any commercial orspecially designed Image Processing algorithm to FFT images stored in anassociated database (not shown). FIG. 22 illustrates such aconfiguration 2200. Though this configuration 2200 depicts only oneexemplary optical configuration (e.g., employing a microscope objective)it will be appreciated that such is applicable to previously discussedconfiguration variants herein.

[0296] The configuration 2200 defines a direct imaging opticalcorrelator as opposed to conventional FT-pair lens configuration usedfor crude-resolution optical correlation and processing. Thisconfiguration 2200 also obviates problems limiting image frequenciessince the intrinsic filtration of the k-space image field defines thepass band. This implies that correlated information fills thenecessary/sufficient conditions for about 100% correlation. This isunlike conventional image processing of spatial/frequency transformswhich are decoded (actually reverse transformed) for comparison,correlation and imaging for inspection of the created image.

[0297]FIG. 23 illustrates an alternative configuration 2300 that definesthat a cataloged image of an existing FFT be projected to a display2310, and superimposed with an image at sensor 2320 to achieve acomparative correlation. The configuration 2300 illustrates that thedisplay device 2310 (e.g., LCD, etc.) displays (is “programmed” with) animage of the FFT of a given object. The displayed FFT image is backprojected into a k-space volume of the device at 2330 and issubsequently imaged in a superposition with an object from a focal planeat 2340. The superposition of actual FFT (frequency fields) achievesvarious aspects of the present invention. In one aspect, it is aprojection of two fields (or more) that are directly correlated at theimager 2320 and defines a 100 percent correlation (or thereabout) inFourier-space which obviates or mitigates requirements for inversetransform matching for correlation. It also obviates or mitigatesassociated frequency errors and uncertainty (i.e., “noise”) since thetransmitted (or rather projected) FFT fields derive from an intrinsick-space pass-band filtration in accordance with the present invention.

[0298] Such correlations can be employed to directly identify or verifythat a database object exists in the field of view, or prove that nosuch object appeared in the field of view. This is achieved when theFFT-display is “programmed” with the image of the FFT of a particulardatabase cataloged object and that FFT projection is superposed withthat of the object in the focal plane at 2340. The superposition isadditive if the same FFT frequency components exist in each of thesuperposed components resulting in a unique correlation-feature seen bythe imager at 2320. This correlation-feature defines a “match” or“correlation” of the superposed fields and is characterized by arecognizable digital “glow” or “brightness enhancement” called“sparkle.” Sparkle being characterized as a defined “spike” or maximumin the superposed frequency components at a given center frequencywithin the k-space pass band. Such spikes define a correlation at thatfrequency. If they do not correlate then there is typically no“sparkle.” The correlation and identification of objects with catalogeddatabase objects is generally immediate and independent of an object'sspatial position or size since these parameters do not affect theobject's transmitted frequency components. Images of the object orobjects in the field of view can (but are not limited to) be capturedfor storage, processing, and/or visually inspected in real time bydirect observation.

[0299] In the foregoing discussion relating to FIG. 24, “objects” referto anything suitably placed in a focal plane to be imaged. This includes(but is not limited to) objects that are either externally illuminatedvia transmissive or reflective illumination or self-illuminated (e.g.,fluorescent or phosphorescent through appropriate excitation). Thisincludes (but is not limited to) any objects, subjects, segments orparts of objects, or features of objects (either single or multiple suchfeatures). Examples include (but are not limited to) particles, cells,parts of particles or cells, and features of particles or cells. Thisalso includes (but is not limited to) opaque objects (e.g., particles,semiconductors, features of particles, semi-conductors, and so forth).

[0300]FIG. 24 illustrates a system 2400 for suspended particulatedetection/imaging in gaseous, liquid, transmissive and/or solid mediumsin accordance with an aspect of the present invention. As discussedpreviously, various techniques can be employed to image moving particlessuch as via timing, shutter and strobing processes, for example. Thesetechniques have the effect of capturing an image of “apparently”motionless or “freeze-frame” particles—even though the particlesthemselves may not in fact be motionless. According to this aspect ofthe present invention, various techniques are described for imagingparticles, whereby particle motion is stopped and/or altered in order tofacilitate image capture in accordance with the present invention.

[0301] The system 2400 includes a side view of a chamber 2410 forreceiving particles that can be imaged in accordance with a viewingportal, observation field, transparent opening, or through anappropriate transparent “window” surface 2420 (entire chamber 2410 canbe transparent for viewing). 2420 represents the imaging Field Of Viewof the k-space imaging field at the object plane in the desiredlocation. A top view of the chamber 2410 is illustrated at 2430illustrating a viewing area 2440 for imaging systems adapted inaccordance with the present invention. It is noted that the chamber2410, 2430 can be substantially any volumetric container (e.g., tubular,triangular, cubic, rectangular and so forth), whereas the image field(viewing area) 2420, 2440 can be “vignetted” by various shapes (e.g.,circular, square, rectangular, elliptical, triangle, and so forth). Thechamber 2410 is employed to alter particle motion to facilitate imagingin accordance with the present invention. As will be described in moredetail below, the chamber 2410, 2430 can employ various techniques toslow or advance particles such as electrostatic techniques, magnetictechniques, mechanical techniques, and/or pressure techniques. Inaddition, the chamber 2410, 2430 can be employed with one or more of theillumination techniques previously described such as viastrobe-illumination, for example.

[0302] In one aspect, the chamber 2410 can be employed when a gaseousmedium in which “particles” as previously described are suspended,carried, flowed, or otherwise contained, etc., is introduced into theobservation field 2420 of the instrument. This can be achieved byflowing gaseous medium (e.g., by pump pressure or vacuum pressuredifference) through a transparent tube of appropriate size tomatch/correlate the depth of field (DOF) and field of view (FOV) (roundor rectangular (also square) cross section for observation (imaging) ofa specific volume in real time. This will facilitate thecharacterization of the particulates as described above.

[0303] In another aspect, flowing gaseous medium in which “particles” aspreviously described are suspended, carried, flowed, or otherwisecontained, etc., can be (e.g., if inert and non-explosive) imaged in a“chamber or space or volume” 2410 having flat transparent walls. Thismay also be a transparent tube. The walls of the space are electricallysensitized via some suitably conductive medium such as a coatedtransparent electrode deposited on the wall of the chamber 2410. Anelectric field can be introduced into this coating or electrodematerial. Such an electric field can be energized at desired intervalsin time and, through the action of static charge, will then “capture thesuspended particulates in the volume of the space and cause them tocollect against the transparent wall (electrode) of the space where theycan be imaged by the imaging system and facilitate characterization ofthe particulates as described above. Conversely, it will be appreciatedthat an opaque electrode may be employed in the same manner such thatsuspended particles are captured on that surface and illuminatednon-transmissively for imaging.

[0304] In yet another aspect, a variation in gas pressure can beintroduced into the chamber 2410 at desired intervals in time and,through the action of evacuation or partial evacuation will then“capture” the suspended particulates in the volume of the “space, etc.”and cause them to collect against the transparent wall of the “space,etc.” where they can be imaged by the imaging systems previouslydescribed and allow the characterization of the particulates asdescribed above.

[0305] In still yet another aspect, a gaseous medium is introduced intothe observation field or viewing area 2420 of the chamber 2410, whereinparticles suspended within the gaseous medium may be influenced bymagnetic fields. The “chamber or space or volume” of the chamber 2410can be mounted in such a way as to be within or surrounded by a magneticfield through the space. This may include permanent and/orelectromagnetic devices. This can include coils of conductive material(windings) separate from and/or integral with the “chamber or space orvolume”. A magnetic field can be introduced and can be energized atdesired intervals in time and, through the action of the inducedmagnetic field and will then “capture the suspended particulates in thevolume of the space within the chamber 2410 and cause them to collectagainst the transparent wall of the space where they can be imaged andcharacterized as described above. Conversely, it will be appreciatedthat an opaque electrode may be employed in the same manner such thatsuspended particles are captured on that surface and illuminatednon-transmissively for imaging.

[0306] As can be appreciated, multiple variations can be employed forimaging particles in accordance with electrostatic, magnetic,mechanical, electronic, and/or pressurized motion techniques. Thesevariations include applying electrical, magnetic, and/or pressurized(e.g., liquid pressure, mechanical pressure) forces to opticallytransmissive liquid mediums having particulates contained therein andsubsequently imaging particles as described above. In another aspect,solid materials having particles trapped therein (can be opticallytransmissive solid material or opaque material for surface analysis) maybe manipulated and/or imaged in accordance with the present invention.For example, solid material may be mechanically stopped and/orpositioned (via control system) within the chamber 2410 while particleimaging occurs.

[0307] In another aspect of the present invention, an imaging systemadapted as described above provides high Effective ResolvedMagnification and high Absolute Spatial Resolution among other featuresof, but not limited to, Fiber-Optic (and other wave-guide) structures,materials, fibers, cables, connectors, welds, attachments, fusion,splices, process monitoring, fabrication, and methods that can becombined to provide improved Fiber optic imaging systems and methods.

[0308] The present invention may be configured and disposed in such away as to allow imaging of any of the forgoing Fiber-Optic materialseither or, but not limited to, the ends of fibers or multiple fibers, orbundles of fibers, etc. in such a way as to be essentially but notlimited to directions perpendicular to the direction of propagation ofradiation in the wave-guide. Likewise, the present invention can beconfigured and disposed in such a way as to allow imaging of any of theforgoing Fiber-Optic materials either or, but not limited to, fibers ormultiple fibers, or bundles of fibers, etc. in such a way as to beessentially but not limited to directions parallel to the direction ofpropagation of radiation in the waveguide.

[0309] The Fiber-Optic imaging systems and methods of the presentinvention enable the production of improved images (higher EffectiveResolved Magnification (ERM), improved Absolute Spatial Resolution(ASR), improved depth of field, and the like) leading to the inspectionand identification of Fiber-Optic materials as well as the manipulation,repair, inspection, and classification of Fiber-Optic materials (forexample as normal or abnormal).

[0310] Fiber-Optics as defined in this application include but are notlimited to all optical transmission media of macroscopic, microscopic,and even nanoscopic scale. This is also understood to include singefibers, bundles, cables, single core, multi-core, polarizationpreserving, circular and non-circular core fibers, glass, plastic,quartz, and any other optical material for transmission of radiation ina wave-guide configuration. Since the Fiber-Optic imaging system of thepresent invention can employ a relatively large working distance withthe advantage of higher ERM and ASR than conventional instrumentationhas traditionally allowed, it will enable, easier manipulation, higherefficacy, greater accuracy, and better repair, for example when used asthe imaging component in a splicing or fusion apparatus which requiresprecision and the highest accuracy in positioning of fiber opticcomponents to be “spliced” by fusion welding, bonding, or any othermethod for aligning and joining fiber “ends” into a continuous fiberlength. The present invention is applicable to other Fiber-Optic relatedimaging applications which require accuracy, precision, and highAbsolute Spatial Resolution imaging at a given magnification. Theforegoing can also be applied, but not limited to, automated imagingapplications for inspection, quality control, fabrication, processcontrol, and the like.

[0311] It will therefore also be appreciated that design and definitionapplications of the present invention will also apply to radiation thatincludes, but is not limited to, X-Radiation (also called x-rays,roentgen-radiation, x-brehmstrahlung, synchrotron, etc.) withwavelengths generally within, but not explicitly limited to, thespectral bandwidth approximately between 0.1 Å (Å meaning Angstrom Unitsof wavelength), or 0.00001 micron, and 100 Å, or 0.01 micron. Radiationof this kind is of such short wavelength and high frequency that it isgenerally discussed in terms of Energy expressed in Electron-Volts (eV).Thus the previously defined bandwidth is also defined as being from 100keV for 0.1 Å to 100 eV for 100 Å x-rays.

[0312] It will be further appreciated therefore that radiation of theseparticular wavelengths whose optical path, direction, and/or path lengthcan thus be altered by means of an “optical medium”, surface, material,component, or components, or other such means suitable to radiation ofthat wavelength in the configuration or configurations pertaining to thedirection of such radiation to achieve the desired characteristics inthe present invention) received from the items under examination in theobject field of view.

[0313] X-radiation is generally not directable using conventionalrefractive physical optics of any material at present, (but theforegoing descriptions of an “optical medium” would also apply to suchshould it exist), but optical path length and focusing of x-rays iscurrently possible employing optical systems based on reflective“Grazing Incidence” techniques, and most currently, advanced diffractive“Zone-plate”, and “layered refractive” optics technology.

[0314] With reference to reflective X-ray optics for direction ofX-rays: The main difference between normal incidence optics for visibleand near-, or quasi-visible light wavelengths and X-ray optics consistsof the strong dependence of X-ray reflection on the angle of incidenceof the photons with respect to the surface. Small incident angles makereflection possible in the X-ray band. Such optics are thus called“Grazing Incidence” (GI) optics. The reflecting surface has a lowmicro-roughness (generally less than or equal to 0.5 nm rms). Also, amaterial with high reflectivity for X-ray wavelengths is most useful,such as Gold which has the highest reflectivity between 0.1 keV and 10keV. GI optics make use of the low angles of incidence to effectively“skip” X-ray photons of the surfaces like a stone skipped off a pondsurface. Special optical designs for GI optics have been devised forvarious energy X-rays and can direct and focus this radiation in a wayanalogous to visible light.

[0315] It will be appreciated that an appropriate set of GI optics toact as a primary “condenser” of incident X-rays to an object and also asboth “Objective” and “relay” mirrors analogous to the visible-lightrefractive optical components could be devised to define a given Fieldof View and effective Numerical Aperture in such a way as to directX-rays through an “object” in an object-plane and subsequently throughan intrinsic k-space filter analogous to that previously described. Theexiting X-ray flux, being filtered by the “optical media” through theintrinsic k-space filter as previously described in much the same way asfor visible light would then be directed toward a detector (sensor)designed to be sensitive to X-rays of any desired energy. It isunderstood that resolution, path length, aberration, and other opticalparameters of the incident and focused X-ray “illumination” aredependent strongly on intrinsic parameters such as monochromaticity,collimation, coherence, etc. and that these parameters are controllableby the inclusion of components such as pinholes, physical spatialfilters, and other “optical components” to modify the incident radiationprior to its direction through the “object” and the optical system ofthe invention.

[0316] With reference to Diffractive “zone-plate” optics for X-raydirection and focusing: Since resolution determination in X-raymicroscopy is generally dependent on criteria such as partial coherence,illumination spectrum, etc. current advances in nano-fabricationtechniques has resulted in the development of deposited diffractive“zone-plate” optics (“lenses”) with general Fresnel zone-plate geometrydesigned to diffract and direct incident X-rays much like well knownFresnel lenses do with visible light. The resulting optics cause X-raysto behave essentially with all the general physical parametersunderstood and observed by radiation in the visible spectrum. As such,Zone-plate lenses have been used to create “standard” so-called“high-resolution” X-ray microscopes. These optics have supplanted theuse of reflective optics for this purpose, being generally easier tofabricate and more robust, as well as physically smaller. These currentstate-of-the-art X-ray microscopes have generally employed zoneplate-optics to condense, focus, and direct incident X-rays throughobjects and onto a CCD camera with sensitivity parameters specific tothe incident X-ray energies (wavelengths). These devices are subject tothe same limitations in their wavelength regime as visible light opticalmicroscopes, and thus the present invention can be extended to X-raymicroscopes.

[0317] With reference to “Layered Refractive” optics for X-ray directionand focusing: New and current advances in x-ray optical theory andfabrication technique has resulted in the development of” LayeredRefractive” x-ray optics (“lenses”) with general geometry designed todirect incident X-rays through multiple layers of materials withappropriately designed optically curved surfaces much like well knownlenses for refraction of visible light radiation. The known variousextant designs of “Layered Refractive” x-ray optics cause X-rays tobehave essentially with the general physical parameters understood andobserved by radiation in the visible spectrum incident throughrefractive optical media. This being the case, “Layered Refractive”x-ray lenses can be used to create “high-resolution” X-ray microscopes.These optics can supplant the use of reflective and diffractive opticsfor this purpose. The current state-of-the-art X-ray microscopes havegenerally employed zone plate-optics to condense, focus, and directincident X-rays through objects and onto a CCD camera with sensitivityparameters specific to the incident X-ray energies (wavelengths).Likewise they can employ “Layered Refractive” x-ray optics to do thesame. These devices are subject to the same limitations in theirwavelength regime as visible light optical microscopes, and thus thepresent invention can be extended to X-ray microscopes.

[0318] It will therefore be appreciated in this aspect that anappropriate set of “Layered Refractive” x-ray optics can be devised toact as a primary “condenser” of incident X-rays to an object and also as“Objective” and “relay” optics analogous to the visible-light refractiveoptical components to define a given Field of View and effectiveNumerical Aperture in such a way as to direct X-rays through an “object”in an object-plane and subsequently through an intrinsic k-space filterbetween “objective” and “relay” analogous to that previously described.The exiting X-ray flux, being filtered by the “optical media” throughthe intrinsic k-space filter in much the same way as for visible lightwould then be directed toward a detector (sensor) designed to besensitive to X-rays of any desired energy. It is understood thatresolution, path length, aberration, and other optical parameters of theincident and focused X-ray “illumination” are dependent strongly onintrinsic parameters such as monochromaticity, collimation, coherence,etc. and that these parameters are controllable by the inclusion ofcomponents such as pinholes, physical spatial filters, and other“optical components” to modify the incident radiation prior to itsdirection through the “object” and the optical system of the invention.

[0319] It is noted that X-rays being focused and otherwise directed by“optical media” it is to be understood that the same criteria forblur-circle, resolution, circle-of-least confusion, “chromatic”aberration, and other optical parameters of the radiation aredescribable by such relationships as Fresnel diffraction rules, and theRayleigh criterion for diffraction spot of the focused radiation.

[0320] It will thus be appreciated that the object field of view thusestablished by the image transfer medium, e.g.: an suitable LayeredRefractive lens, Fresnel Zone-plate lens, or appropriate GI optic, isrelated to the position of an object plane that includes one or moreitems under examination (not shown). Such a sensor can be any set ofcurrently extant detectors for resolving count rate, flux, energy,position, incidence time, etc. of X-rays. Common X-ray detectors includeGas ionization, proportional, multiwire and strip, scintillation, energyresolving semiconductor, surface barrier, avalanche or other photodiode,CCD, CMOS, super conducting, microchannel or capillary plate, or othersas may become available. The currently most advanced and useful of suchdetectors for X-ray imaging are CCD and or CMOS sensor arraysspecifically designed to detect and digitize incident X-rays in much thesame ways that visible light sensitive CCD's and CMOS sensors provide.

[0321] Such X-ray detectors could be arranged in such a way as to betherefore analogous to and be disposed in the same manner as opticalsensors. It can be substantially any size, shape and/or technology inany suitable geometry (e.g.: an array sensor, a linear sensor, etc.)including one or more receptors of various sizes and shapes, the one ormore receptors being similarly sized or proportioned to devise arespective sensor to be responsive to incident X-rays directed throughor even reflected or diffracted from the object.

[0322] An aspect of the invention for use with X-rays is thusessentially analogous to that described in the invention for visiblelight. As X-ray flux is thus received from the object field of view, theX-ray sensor provides an output inherent to the detector (e.g.,electrical current, voltage, etc.) that can be displayed directly orprocessed by a computer and can be directed to a local or remote storagesuch as a memory and displayed from the memory via the computer andassociated display. It is noted that local or remote signal processingof the image data received from the sensor can also occur. For example,the output can be converted to electronic data packets and transmittedto a remote system over a network and/or via wireless transmissionssystems and protocols for further analysis and/or display. Similarly,the output can be stored in a local computer memory before beingtransmitted to the subsequent computing system for further analysisand/or display.

[0323] To illustrate some of the concepts herein, the following tablesare provided to highlight some exemplary differences between the presentinvention and conventional microscopic systems. NA stands for numericalaperature, DOF stands for depth of field, WD stands for workingdistance, Mag stands for magnification, and TM stands for totalmagnification (with a 10× eyepiece). Foe example, the following tableshows conventional microscope design parameters: Resolution NA DOF WDObjective TM 2,500 nm 0.10  100 um 22.0 mm  4x  40x 1,000 nm 0.25   16um 10.5 mm 10x 100x   625 nm 0.40 6.25 um 1.20 mm 20x 200x   384 nm 0.652.40 um 0.56 mm 40x 400x   200 nm 1.25 0.64 um 0.15 mm (oil) 100x (oil)1000x

[0324] By comparison to the above table, if a 2.7 micron pixel isemployed, for example, the present invention can provide 2500 nmresolution with about 1.1× magnification, 1000 nm resolution with about2.7× magnification, 625 nm resolution with about 4.32× magnification,384 nm resolution with about 7.03× magnification, and 200 nm resolutionwith about 13.5× (oil) magnification.

[0325] The following tables show a performance comparison betweenconventional imaging systems and imaging systems of the presentinvention. The imaging system of the present invention in this exampleemploys a lens design diameter about 25 mm. Optimum conventionalresolution occurs at approximately 1000×NA (See standard opticsliterature).

Example Present Invention Optical Parameters

[0326] Resolution NA DOF WD Mag 2,500 nm 0.10  100 um 125 mm  1x 1,000nm 0.25   16 um 48 mm 3x   625 nm 0.40 6.25 um 28 mm 4x   384 nm 0.652.40 um 14 mm 7x

Conventional Microscope Optical Parameters

[0327] Mag Req'd for Resolution NA DOF WD resolution (10x eyepiece)2,500 nm 0.10  100 um 125 mm  100x 1,000 nm 0.25   16 um 48 mm 250x  625 nm 0.40 6.25 um 28 mm 400x   384 nm 0.65 2.40 um 14 mm 650x

[0328] To achieve a resolution of 2,500 nm, the Conventional Microscoperequires a 100× magnification and thus has a resolution performance of{fraction (1/100)} of that of the imaging system of the presentinvention. To achieve a resolution of 2,500 nm, the ConventionalMicroscope requires a 100× magnification and thus has a, resolutionperformance of {fraction (1/80)} of that of the imaging system of thepresent invention. To achieve a resolution of 2,500 nm, the ConventionalMicroscope requires a 100× magnification and thus has a resolutionperformance of {fraction (1/100)} of that of the imaging system of thepresent invention. To achieve a resolution of 384 nm, the ConventionalMicroscope requires a 650× magnification and thus has a resolutionperformance of {fraction (1/93)} of that of the imaging system of thepresent invention.

[0329] Thus, by observing the above tables, it is illustrated thatresolution in the present invention can be achieved with about 100 timesless magnification than conventional systems when viewed in terms of a2.7 micron pixel sensor. This facilitates such features as greatlyimproved working distances for example along with allowing highperformance, low cost, compact, modular, and robust microscopy systemsto be employed.

[0330] What has been described above are preferred aspects of thepresent invention. It is, of course, not possible to describe everyconceivable combination of components or methodologies for purposes ofdescribing the present invention, but one of ordinary skill in the artwill recognize that many further combinations and permutations of thepresent invention are possible. Accordingly, the present invention isintended to embrace all such alterations, modifications and variationsthat fall within the spirit and scope of the appended claims.

What is claimed is:
 1. A digital image comprising a plurality of imagepixels, each image pixel comprising information from about one sensorpixel, each sensor pixel comprising substantially all information fromabout one associated diffraction limited spot in an object plane.
 2. Thedigital image of claim 1 comprising at least about 2,000 image pixels.3. The digital image of claim 1, wherein each sensor pixel comprises atleast about 60% of the information from an associated diffractionlimited spot.
 4. The digital image of claim 1, wherein each sensor pixelcomprises at least about 70% of the information from an associateddiffraction limited spot.
 5. The digital image of claim 1, wherein eachsensor pixel comprises at least about 95% of the information from anassociated diffraction limited spot.
 6. A digital image comprising aplurality of image pixels, each image pixel comprising substantially allinformation comprised by one diffraction limited spot in an objectplane.
 7. The digital image of claim 6 comprising at least about 10,000image pixels.
 8. The digital image of claim 6, wherein each image pixelcomprises at least about 60% of the information from an associateddiffraction limited spot.
 9. The digital image of claim 6, wherein eachimage pixel comprises at least about 80% of the information from anassociated diffraction limited spot.
 10. A method of making a digitalimage, comprising capturing object data on a pixelated sensor, whereinsubstantially all object data comprised in each diffraction limited spotin the object plane is projected onto about one associated pixel on thepixelated sensor; and forming a digital image comprising image pixels,each image pixel displaying image data from about one sensor pixel. 11.The method of claim 10, wherein each pixel on the pixelated sensorcomprises at least about 60% of the object data from the associateddiffraction limited spot.
 12. The method of claim 10, wherein each pixelon the pixelated sensor comprises at least about 70% of the object datafrom the associated diffraction limited spot.
 13. The method of claim10, wherein a ratio of diffraction limited spot size in the object planeto projected pixel size in the object plane is from about 1:1.9 to about1.9:1.
 14. The method of claim 10, wherein substantially all object datais captured through a multiple lens configuration, the multiple lensconfiguration comprising a first lens positioned toward the object planeand a second lens positioned toward the pixelated sensor, the first lenssized to have a focal length smaller than the second lens.
 15. A methodof increasing the signal to noise ratio in making a digital image,comprising collecting substantially all spatial frequencies of interestfrom a diffraction limited spot in the object plane by about one pixelon a sensor.
 16. The method of claim 15, wherein each pixel on thesensor collects at least about 60% of the spatial frequencies ofinterest from an associated diffraction limited spot.
 17. The method ofclaim 15, wherein each pixel on the sensor collects at least about 80%of the spatial frequencies of interest from an associated diffractionlimited spot.
 18. The method of claim 15, wherein a ratio of diffractionlimited spot size in the object plane to projected pixel size in theobject plane is from about 1:1.9 to about 1.9:1.
 19. The method of claim15, wherein substantially all spatial frequencies of interest arecollected through a multiple lens configuration, the multiple lensconfiguration comprising a first lens positioned toward the object planeand a second lens positioned toward the sensor, the first lens sized tohave a focal length smaller than the second lens.
 20. A method offorming a digital image, comprising capturing object data on a sensorcomprising pixels, wherein each pixel on the sensor receivessubstantially all object data comprised in an associated diffractionlimited spot in the object plane and each pixel generates image data;and applying Nyquist criterion to the image data generated by the pixelsto form the digital image.
 21. The method of claim 20, wherein eachpixel on the sensor receives at least about 60% of the object datacomprised in an associated diffraction limited spot.
 22. The method ofclaim 20, wherein a ratio of diffraction limited spot size in the objectplane to projected pixel size in the object plane is from about 1:1.9 toabout 1.9:1.
 23. The method of claim 20, wherein substantially allobject data is captured through a multiple lens configuration, themultiple lens configuration comprising a first lens positioned towardthe object plane and a second lens positioned toward the sensor, thefirst lens sized to have a focal length smaller than the second lens.